v1.5.0

CHANGELOG.md

@@ -2,7 +2,14 @@
 
 ### New Features
 
-- Track token position in AST Token node
+- Track start and end text positions for tokens and rules in AST node structures (#27)
+- Add warnings for shift/reduce conflicts to log file (#25)
+- Add -w command line switch to treat warnings as errors and output to stderr (#26)
+- Add rule field aliases (#24)
+
+### Improvements
+
+- Show line numbers of rules on conflict (#23)
 
 ## v1.4.0
 

assets/parser.c.erb

@@ -226,7 +226,10 @@ typedef struct
     /** Number of bytes of input text used to match. */
     size_t length;
 
-    /** Input text position delta. */
+    /** Input text position delta to end of token. */
+    <%= @grammar.prefix %>position_t end_delta_position;
+
+    /** Input text position delta to next code point after token end. */
     <%= @grammar.prefix %>position_t delta_position;
 
     /** Accepting lexer state from the match. */
@@ -358,6 +361,7 @@ static size_t find_longest_match(<%= @grammar.prefix %>context_t * context,
             if (transition_state != INVALID_LEXER_STATE_ID)
             {
                 attempt_match.length += code_point_length;
+                attempt_match.end_delta_position = attempt_match.delta_position;
                 if (code_point == '\n')
                 {
                     attempt_match.delta_position.row++;
@@ -490,11 +494,22 @@ static size_t attempt_lex_token(<%= @grammar.prefix %>context_t * context, <%= @
         }
         token_info.token = token_to_accept;
         token_info.length = match_info.length;
+        if (match_info.end_delta_position.row != 0u)
+        {
+            token_info.end_position.row = token_info.position.row + match_info.end_delta_position.row;
+            token_info.end_position.col = match_info.end_delta_position.col;
+        }
+        else
+        {
+            token_info.end_position.row = token_info.position.row;
+            token_info.end_position.col = token_info.position.col + match_info.end_delta_position.col;
+        }
         *out_token_info = token_info;
         return P_SUCCESS;
 
     case P_EOF:
         token_info.token = TOKEN___EOF;
+        token_info.end_position = token_info.position;
         *out_token_info = token_info;
         return P_SUCCESS;
 
@@ -551,6 +566,9 @@ size_t <%= @grammar.prefix %>lex(<%= @grammar.prefix %>context_t * context, <%=
  * Parser
  *************************************************************************/
 
+/** Invalid position value. */
+#define INVALID_POSITION (<%= @grammar.prefix %>position_t){0xFFFFFFFFu, 0xFFFFFFFFu}
+
 /** Reduce ID type. */
 typedef <%= get_type_for(@parser.reduce_table.size) %> reduce_id_t;
 
@@ -666,6 +684,14 @@ typedef struct
 <% end %>
 } state_value_t;
 
+/** Common AST node structure. */
+typedef struct
+{
+    <%= @grammar.prefix %>position_t position;
+    <%= @grammar.prefix %>position_t end_position;
+    void * fields[];
+} ASTNode;
+
 /** Parser shift table. */
 static const shift_t parser_shift_table[] = {
 <%   @parser.shift_table.each do |shift| %>
@@ -949,9 +975,10 @@ size_t <%= @grammar.prefix %>parse(<%= @grammar.prefix %>context_t * context)
                 /* We shifted a token, mark it consumed. */
 <% if @grammar.ast %>
                 <%= @grammar.ast_prefix %>Token<%= @grammar.ast_suffix %> * token_ast_node = malloc(sizeof(<%= @grammar.ast_prefix %>Token<%= @grammar.ast_suffix %>));
+                token_ast_node->position = token_info.position;
+                token_ast_node->end_position = token_info.end_position;
                 token_ast_node->token = token;
                 token_ast_node->pvalue = token_info.pvalue;
-                token_ast_node->position = token_info.position;
                 state_values_stack_index(&statevalues, -1)->ast_node = token_ast_node;
 <% else %>
                 state_values_stack_index(&statevalues, -1)->pvalue = token_info.pvalue;
@@ -984,22 +1011,43 @@ size_t <%= @grammar.prefix %>parse(<%= @grammar.prefix %>context_t * context)
             }
             else if (parser_reduce_table[reduce_index].n_states > 0)
             {
-                void ** node_fields = calloc(parser_reduce_table[reduce_index].rule_set_node_field_array_size, sizeof(void *));
+                size_t n_fields = parser_reduce_table[reduce_index].rule_set_node_field_array_size;
+                ASTNode * node = (ASTNode *)malloc(sizeof(ASTNode) + n_fields * sizeof(void *));
+                node->position = INVALID_POSITION;
+                node->end_position = INVALID_POSITION;
+                for (size_t i = 0; i < n_fields; i++)
+                {
+                    node->fields[i] = NULL;
+                }
                 if (parser_reduce_table[reduce_index].rule_set_node_field_index_map == NULL)
                 {
                     for (size_t i = 0; i < parser_reduce_table[reduce_index].n_states; i++)
                     {
-                        node_fields[i] = state_values_stack_index(&statevalues, -(int)parser_reduce_table[reduce_index].n_states + (int)i)->ast_node;
+                        node->fields[i] = state_values_stack_index(&statevalues, -(int)parser_reduce_table[reduce_index].n_states + (int)i)->ast_node;
                     }
                 }
                 else
                 {
                     for (size_t i = 0; i < parser_reduce_table[reduce_index].n_states; i++)
                     {
-                        node_fields[parser_reduce_table[reduce_index].rule_set_node_field_index_map[i]] = state_values_stack_index(&statevalues, -(int)parser_reduce_table[reduce_index].n_states + (int)i)->ast_node;
+                        node->fields[parser_reduce_table[reduce_index].rule_set_node_field_index_map[i]] = state_values_stack_index(&statevalues, -(int)parser_reduce_table[reduce_index].n_states + (int)i)->ast_node;
                     }
                 }
-                reduced_parser_node = node_fields;
+                bool position_found = false;
+                for (size_t i = 0; i < n_fields; i++)
+                {
+                    ASTNode * child = (ASTNode *)node->fields[i];
+                    if ((child != NULL) && <%= @grammar.prefix %>position_valid(child->position))
+                    {
+                        if (!position_found)
+                        {
+                            node->position = child->position;
+                            position_found = true;
+                        }
+                        node->end_position = child->end_position;
+                    }
+                }
+                reduced_parser_node = node;
             }
             else
             {

assets/parser.d.erb

@@ -8,6 +8,8 @@
 module <%= @grammar.modulename %>;
 <% end %>
 
+import core.stdc.stdlib : malloc;
+
 /**************************************************************************
  * User code blocks
  *************************************************************************/
@@ -61,6 +63,15 @@ public struct <%= @grammar.prefix %>position_t
 
     /** Input text column (0-based). */
     uint col;
+
+    /** Invalid position value. */
+    enum INVALID = <%= @grammar.prefix %>position_t(0xFFFF_FFFF, 0xFFFF_FFFF);
+
+    /** Return whether the position is valid. */
+    public @property bool valid()
+    {
+        return row != 0xFFFF_FFFFu;
+    }
 }
 
 <% if @grammar.ast %>
@@ -77,12 +88,22 @@ public union <%= @grammar.prefix %>value_t
 <% end %>
 
 <% if @grammar.ast %>
+/** Common AST node structure. */
+private struct ASTNode
+{
+    <%= @grammar.prefix %>position_t position;
+    <%= @grammar.prefix %>position_t end_position;
+    void *[0] fields;
+}
+
 /** AST node types. @{ */
 public struct <%= @grammar.ast_prefix %>Token<%= @grammar.ast_suffix %>
 {
+    /* ASTNode fields must be present in the same order here. */
+    <%= @grammar.prefix %>position_t position;
+    <%= @grammar.prefix %>position_t end_position;
     <%= @grammar.prefix %>token_t token;
     <%= @grammar.prefix %>value_t pvalue;
-    <%= @grammar.prefix %>position_t position;
 }
 
 <%   @parser.rule_sets.each do |name, rule_set| %>
@@ -90,6 +111,8 @@ public struct <%= @grammar.ast_prefix %>Token<%= @grammar.ast_suffix %>
 <%     next if rule_set.optional? %>
 public struct <%= @grammar.ast_prefix %><%= name %><%= @grammar.ast_suffix %>
 {
+    <%= @grammar.prefix %>position_t position;
+    <%= @grammar.prefix %>position_t end_position;
 <%     rule_set.ast_fields.each do |fields| %>
     union
     {
@@ -107,9 +130,12 @@ public struct <%= @grammar.ast_prefix %><%= name %><%= @grammar.ast_suffix %>
 /** Lexed token information. */
 public struct <%= @grammar.prefix %>token_info_t
 {
-    /** Text position where the token was found. */
+    /** Text position of first code point in token. */
     <%= @grammar.prefix %>position_t position;
 
+    /** Text position of last code point in token. */
+    <%= @grammar.prefix %>position_t end_position;
+
     /** Number of input bytes used by the token. */
     size_t length;
 
@@ -373,7 +399,10 @@ private struct lexer_match_info_t
     /** Number of bytes of input text used to match. */
     size_t length;
 
-    /** Input text position delta. */
+    /** Input text position delta to end of token. */
+    <%= @grammar.prefix %>position_t end_delta_position;
+
+    /** Input text position delta to next code point after token end. */
     <%= @grammar.prefix %>position_t delta_position;
 
     /** Accepting lexer state from the match. */
@@ -501,6 +530,7 @@ private size_t find_longest_match(<%= @grammar.prefix %>context_t * context,
             if (transition_state != INVALID_LEXER_STATE_ID)
             {
                 attempt_match.length += code_point_length;
+                attempt_match.end_delta_position = attempt_match.delta_position;
                 if (code_point == '\n')
                 {
                     attempt_match.delta_position.row++;
@@ -633,11 +663,22 @@ private size_t attempt_lex_token(<%= @grammar.prefix %>context_t * context, <%=
         }
         token_info.token = token_to_accept;
         token_info.length = match_info.length;
+        if (match_info.end_delta_position.row != 0u)
+        {
+            token_info.end_position.row = token_info.position.row + match_info.end_delta_position.row;
+            token_info.end_position.col = match_info.end_delta_position.col;
+        }
+        else
+        {
+            token_info.end_position.row = token_info.position.row;
+            token_info.end_position.col = token_info.position.col + match_info.end_delta_position.col;
+        }
         *out_token_info = token_info;
         return P_SUCCESS;
 
     case P_EOF:
         token_info.token = TOKEN___EOF;
+        token_info.end_position = token_info.position;
         *out_token_info = token_info;
         return P_SUCCESS;
 
@@ -997,7 +1038,7 @@ public size_t <%= @grammar.prefix %>parse(<%= @grammar.prefix %>context_t * cont
             {
                 /* We shifted a token, mark it consumed. */
 <% if @grammar.ast %>
-                <%= @grammar.ast_prefix %>Token<%= @grammar.ast_suffix %> * token_ast_node = new <%= @grammar.ast_prefix %>Token<%= @grammar.ast_suffix %>(token, token_info.pvalue, token_info.position);
+                <%= @grammar.ast_prefix %>Token<%= @grammar.ast_suffix %> * token_ast_node = new <%= @grammar.ast_prefix %>Token<%= @grammar.ast_suffix %>(token_info.position, token_info.end_position, token, token_info.pvalue);
                 statevalues[$-1].ast_node = token_ast_node;
 <% else %>
                 statevalues[$-1].pvalue = token_info.pvalue;
@@ -1030,26 +1071,43 @@ public size_t <%= @grammar.prefix %>parse(<%= @grammar.prefix %>context_t * cont
             }
             else if (parser_reduce_table[reduce_index].n_states > 0)
             {
-                void *[] node_fields = new void *[parser_reduce_table[reduce_index].rule_set_node_field_array_size];
-                foreach (i; 0..parser_reduce_table[reduce_index].rule_set_node_field_array_size)
+                size_t n_fields = parser_reduce_table[reduce_index].rule_set_node_field_array_size;
+                ASTNode * node = cast(ASTNode *)malloc(ASTNode.sizeof + n_fields * (void *).sizeof);
+                node.position = <%= @grammar.prefix %>position_t.INVALID;
+                node.end_position = <%= @grammar.prefix %>position_t.INVALID;
+                foreach (i; 0..n_fields)
                 {
-                    node_fields[i] = null;
+                    node.fields[i] = null;
                 }
                 if (parser_reduce_table[reduce_index].rule_set_node_field_index_map is null)
                 {
                     foreach (i; 0..parser_reduce_table[reduce_index].n_states)
                     {
-                        node_fields[i] = statevalues[$ - parser_reduce_table[reduce_index].n_states + i].ast_node;
+                        node.fields[i] = statevalues[$ - parser_reduce_table[reduce_index].n_states + i].ast_node;
                     }
                 }
                 else
                 {
                     foreach (i; 0..parser_reduce_table[reduce_index].n_states)
                     {
-                        node_fields[parser_reduce_table[reduce_index].rule_set_node_field_index_map[i]] = statevalues[$ - parser_reduce_table[reduce_index].n_states + i].ast_node;
+                        node.fields[parser_reduce_table[reduce_index].rule_set_node_field_index_map[i]] = statevalues[$ - parser_reduce_table[reduce_index].n_states + i].ast_node;
                     }
                 }
-                reduced_parser_node = node_fields.ptr;
+                bool position_found = false;
+                foreach (i; 0..n_fields)
+                {
+                    ASTNode * child = cast(ASTNode *)node.fields[i];
+                    if (child && child.position.valid)
+                    {
+                        if (!position_found)
+                        {
+                            node.position = child.position;
+                            position_found = true;
+                        }
+                        node.end_position = child.end_position;
+                    }
+                }
+                reduced_parser_node = node;
             }
             else
             {

assets/parser.h.erb

@@ -52,6 +52,9 @@ typedef struct
     uint32_t col;
 } <%= @grammar.prefix %>position_t;
 
+/** Return whether the position is valid. */
+#define <%= @grammar.prefix %>position_valid(p) ((p).row != 0xFFFFFFFFu)
+
 /** User header code blocks. */
 <%= @grammar.code_blocks.fetch("header", "") %>
 
@@ -72,9 +75,11 @@ typedef union
 /** AST node types. @{ */
 typedef struct <%= @grammar.ast_prefix %>Token<%= @grammar.ast_suffix %>
 {
+    /* ASTNode fields must be present in the same order here. */
+    <%= @grammar.prefix %>position_t position;
+    <%= @grammar.prefix %>position_t end_position;
     <%= @grammar.prefix %>token_t token;
     <%= @grammar.prefix %>value_t pvalue;
-    <%= @grammar.prefix %>position_t position;
 } <%= @grammar.ast_prefix %>Token<%= @grammar.ast_suffix %>;
 
 <%   @parser.rule_sets.each do |name, rule_set| %>
@@ -88,6 +93,8 @@ struct <%= name %>;
 <%     next if rule_set.optional? %>
 typedef struct <%= @grammar.ast_prefix %><%= name %><%= @grammar.ast_suffix %>
 {
+    <%= @grammar.prefix %>position_t position;
+    <%= @grammar.prefix %>position_t end_position;
 <%     rule_set.ast_fields.each do |fields| %>
     union
     {
@@ -105,9 +112,12 @@ typedef struct <%= @grammar.ast_prefix %><%= name %><%= @grammar.ast_suffix %>
 /** Lexed token information. */
 typedef struct
 {
-    /** Text position where the token was found. */
+    /** Text position of first code point in token. */
     <%= @grammar.prefix %>position_t position;
 
+    /** Text position of last code point in token. */
+    <%= @grammar.prefix %>position_t end_position;
+
     /** Number of input bytes used by the token. */
     size_t length;
 

doc/user_guide.md

@@ -15,6 +15,7 @@ Propane is a LALR Parser Generator (LPG) which:
   * generates a table-driven shift/reduce parser to parse input in linear time
   * targets C or D language outputs
   * optionally supports automatic full AST generation
+  * tracks input text start and end positions for all matched tokens/rules
   * is MIT-licensed
   * is distributable as a standalone Ruby script
 
@@ -35,9 +36,14 @@ Propane is typically invoked from the command-line as `./propane`.
 
     Usage: ./propane [options] <input-file> <output-file>
     Options:
-      --log LOG   Write log file
-      --version   Show program version and exit
-      -h, --help  Show this usage and exit
+      -h, --help  Show this usage and exit.
+      --log LOG   Write log file. This will show all parser states and their
+                  associated shifts and reduces. It can be helpful when
+                  debugging a grammar.
+      --version   Show program version and exit.
+      -w          Treat warnings as errors. This option will treat shift/reduce
+                  conflicts as fatal errors and will print them to stderr in
+                  addition to the log file.
 
 The user must specify the path to a Propane input grammar file and a path to an
 output file.
@@ -228,15 +234,15 @@ drop /\\s+/;
 
 Start -> Items;
 
-Items -> Item ItemsMore;
+Items -> Item:item ItemsMore;
 Items -> ;
 
-ItemsMore -> comma Item ItemsMore;
+ItemsMore -> comma Item:item ItemsMore;
 ItemsMore -> ;
 
 Item -> a;
 Item -> b;
-Item -> lparen Item rparen;
+Item -> lparen Item:item rparen;
 Item -> Dual;
 
 Dual -> One Two;
@@ -257,24 +263,24 @@ Start * start = p_result(&context);
 assert(start.pItems1 !is null);
 assert(start.pItems !is null);
 Items * items = start.pItems;
-assert(items.pItem !is null);
-assert(items.pItem.pToken1 !is null);
-assert_eq(TOKEN_a, items.pItem.pToken1.token);
-assert_eq(11, items.pItem.pToken1.pvalue);
+assert(items.item !is null);
+assert(items.item.pToken1 !is null);
+assert_eq(TOKEN_a, items.item.pToken1.token);
+assert_eq(11, items.item.pToken1.pvalue);
 assert(items.pItemsMore !is null);
 ItemsMore * itemsmore = items.pItemsMore;
-assert(itemsmore.pItem !is null);
-assert(itemsmore.pItem.pItem !is null);
-assert(itemsmore.pItem.pItem.pItem !is null);
-assert(itemsmore.pItem.pItem.pItem.pToken1 !is null);
-assert_eq(TOKEN_b, itemsmore.pItem.pItem.pItem.pToken1.token);
-assert_eq(22, itemsmore.pItem.pItem.pItem.pToken1.pvalue);
+assert(itemsmore.item !is null);
+assert(itemsmore.item.item !is null);
+assert(itemsmore.item.item.item !is null);
+assert(itemsmore.item.item.item.pToken1 !is null);
+assert_eq(TOKEN_b, itemsmore.item.item.item.pToken1.token);
+assert_eq(22, itemsmore.item.item.item.pToken1.pvalue);
 assert(itemsmore.pItemsMore !is null);
 itemsmore = itemsmore.pItemsMore;
-assert(itemsmore.pItem !is null);
-assert(itemsmore.pItem.pToken1 !is null);
-assert_eq(TOKEN_b, itemsmore.pItem.pToken1.token);
-assert_eq(22, itemsmore.pItem.pToken1.pvalue);
+assert(itemsmore.item !is null);
+assert(itemsmore.item.pToken1 !is null);
+assert_eq(TOKEN_b, itemsmore.item.pToken1.token);
+assert_eq(22, itemsmore.item.pToken1.pvalue);
 assert(itemsmore.pItemsMore is null);
 ```
 
@@ -502,7 +508,7 @@ tokenid str;
   mystringvalue = "";
   $mode(string);
 >>
-string: /[^"]+/ << mystringvalue += match; >>
+string: /[^"]+/ << mystringvalue ~= match; >>
 string: /"/ <<
   $mode(default);
   return $token(str);
@@ -601,6 +607,10 @@ This can be changed with the `start` statement.
 The grammar file must define a rule with the name of the start rule name which
 will be used as the top-level starting rule that the parser attempts to reduce.
 
+Rule statements are composed of the name of the rule, a `->` token, the fields
+defining the rule pattern that must be matched, and a terminating semicolon or
+user code block.
+
 Example:
 
 ```
@@ -629,9 +639,13 @@ E4 -> lparen E1 rparen << $$ = $2; >>
 
 This example uses the default start rule name of `Start`.
 
-A parser rule has zero or more terms on the right side of its definition.
-Each of these terms is either a token name or a rule name.
-A term can be immediately followed by a `?` character to signify that it is
+A parser rule has zero or more fields on the right side of its definition.
+Each of these fields is either a token name or a rule name.
+A field can optionally be followed by a `:` and then a field alias name.
+If present, the field alias name is used to refer to the field value in user
+code blocks, or if AST mode is active, the field alias name is used as the
+field name in the generated AST node structure.
+A field can be immediately followed by a `?` character to signify that it is
 optional.
 Another example:
 
@@ -641,14 +655,16 @@ token private;
 token int;
 token ident /[a-zA-Z_][a-zA-Z_0-9]*/;
 token semicolon /;/;
-IntegerDeclaration -> Visibility? int ident semicolon;
+IntegerDeclaration -> Visibility? int ident:name semicolon;
 Visibility -> public;
 Visibility -> private;
 ```
 
-In a parser rule code block, parser values for the right side terms are
-accessible as `$1` for the first term's parser value, `$2` for the second
-term's parser value, etc...
+In a parser rule code block, parser values for the right side fields are
+accessible as `$1` for the first field's parser value, `$2` for the second
+field's parser value, etc...
+For the `IntegerDeclaration` rule, the third field value can also be referred
+to as `${name}`.
 The `$$` symbol accesses the output parser value for this rule.
 The above examples demonstrate how the parser values for the rule components
 can be used to produce the parser value for the accepted rule.
@@ -762,6 +778,13 @@ A pointer to this instance is passed to the generated functions.
 The `p_position_t` structure contains two fields `row` and `col`.
 These fields contain the 0-based row and column describing a parser position.
 
+For D targets, the `p_position_t` structure can be checked for validity by
+querying the `valid` property.
+
+For C targets, the `p_position_t` structure can be checked for validity by
+calling `p_position_valid(pos)` where `pos` is a `p_position_t` structure
+instance.
+
 ### AST Node Types
 
 If AST generation mode is enabled, a structure type for each rule will be
@@ -772,13 +795,26 @@ AST node which refers to a raw parser token rather than a composite rule.
 
 #### AST Node Fields
 
-A `Token` node has two fields:
+All AST nodes have a `position` field specifying the text position of the
+beginning of the matched token or rule, and an `end_position` field specifying
+the text position of the end of the matched token or rule.
+Each of these fields are instances of the `p_position_t` structure.
+
+A `Token` node will always have a valid `position` and `end_position`.
+A rule node may not have valid positions if the rule allows for an empty match.
+In this case the `position` structure should be checked for validity before
+using it.
+For C targets this can be accomplished with
+`if (p_position_valid(node->position))` and for D targets this can be
+accomplished with `if (node.position.valid)`.
+
+A `Token` node has the following additional fields:
 
   * `token` which specifies which token was parsed (one of `TOKEN_*`)
   * `pvalue` which specifies the parser value for the token. If a lexer user
   code block assigned to `$$`, the assigned value will be stored here.
 
-The other generated AST node structures have fields generated based on the
+AST node structures for rules contain generated fields based on the
 right hand side components specified for all rules of a given name.
 
 In this example:
@@ -802,7 +838,7 @@ The `Items` structure will have fields:
 
 If a rule can be empty (for example in the second `Items` rule above), then
 an instance of a pointer to that rule's generated AST node will be null if the
-parser matches the empty rule definition.
+parser matches the empty rule pattern.
 
 The non-positional AST node field pointer will not be generated if there are
 multiple positions in which an instance of the node it points to could be
@@ -823,6 +859,19 @@ If the first rule is matched, then `pOne1` and `pTwo2` will be non-null while
 `pTwo1` and `pOne2` will be null.
 If the second rule is matched instead, then the opposite would be the case.
 
+If a field alias is present in a rule definition, an additional field will be
+generated in the AST node with the field alias name.
+For example:
+
+```
+Exp -> Exp:left plus ExpB:right;
+```
+
+In the generated `Exp` structure, the fields `pExp`, `pExp1`, and `left` will
+all point to the same child node (an instance of the `Exp` structure), and the
+fields `pExpB`, `pExpB3`, and `right` will all point to the same child node
+(an instance of the `ExpB` structure).
+
 ##> Functions
 
 ### `p_context_init`
@@ -859,6 +908,24 @@ p_context_init(&context, input, input_length);
 size_t result = p_parse(&context);
 ```
 
+### `p_position_valid`
+
+The `p_position_valid()` function is only generated for C targets.
+it is used to determine whether or not a `p_position_t` structure is valid.
+
+Example:
+
+```
+if (p_position_valid(node->position))
+{
+    ....
+}
+```
+
+For D targets, rather than using `p_position_valid()`, the `valid` property
+function of the `p_position_t` structure can be queried
+(e.g. `if (node.position.valid)`).
+
 ### `p_result`
 
 The `p_result()` function can be used to retrieve the final parse value after

extra/vim/syntax/propane.vim

@@ -17,6 +17,9 @@ syn region propaneTarget matchgroup=propaneDelimiter start="<<" end=">>$" contai
 
 syn match propaneComment "#.*"
 syn match propaneOperator "->"
+syn match propaneFieldAlias ":[a-zA-Z0-9_]\+" contains=propaneFieldOperator
+syn match propaneFieldOperator ":" contained
+syn match propaneOperator "?"
 syn keyword propaneKeyword ast ast_prefix ast_suffix drop module prefix ptype start token tokenid
 
 syn region propaneRegex start="/" end="/" skip="\\/"
@@ -25,4 +28,6 @@ hi def link propaneComment Comment
 hi def link propaneKeyword Keyword
 hi def link propaneRegex String
 hi def link propaneOperator Operator
+hi def link propaneFieldOperator Operator
 hi def link propaneDelimiter Delimiter
+hi def link propaneFieldAlias Identifier

lib/propane/cli.rb

@@ -4,11 +4,11 @@ class Propane
     USAGE = <<EOF
 Usage: #{$0} [options] <input-file> <output-file>
 Options:
+  -h, --help  Show this usage and exit.
   --log LOG   Write log file. This will show all parser states and their
               associated shifts and reduces. It can be helpful when
               debugging a grammar.
   --version   Show program version and exit.
-  -h, --help  Show this usage and exit.
   -w          Treat warnings as errors. This option will treat shift/reduce
               conflicts as fatal errors and will print them to stderr in
               addition to the log file.

lib/propane/generator.rb

@@ -276,6 +276,19 @@ class Propane
             "statevalues[$-1-n_states+#{index}].pvalue.v_#{rule.components[index - 1].ptypename}"
           end
         end
+        code = code.gsub(/\$\{(\w+)\}/) do |match|
+          aliasname = $1
+          if index = rule.aliases[aliasname]
+            case @language
+            when "c"
+              "state_values_stack_index(statevalues, -(int)n_states + #{index})->pvalue.v_#{rule.components[index].ptypename}"
+            when "d"
+              "statevalues[$-n_states+#{index}].pvalue.v_#{rule.components[index].ptypename}"
+            end
+          else
+            raise Error.new("Field alias '#{aliasname}' not found")
+          end
+        end
       else
         code = code.gsub(/\$\$/) do |match|
           if @grammar.ast

lib/propane/grammar.rb

@@ -198,7 +198,7 @@ class Propane
         if @ast && ptypename
           raise Error.new("Multiple ptypes are unsupported in AST mode")
         end
-        md = consume!(/((?:#{IDENTIFIER_REGEX}\??\s*)*)\s*/, "expected rule component list")
+        md = consume!(/((?:#{IDENTIFIER_REGEX}(?::#{IDENTIFIER_REGEX})?\??\s*)*)\s*/, "expected rule component list")
         components = md[1].strip.split(/\s+/)
         if @ast
           consume!(/;/, "expected `;'")

lib/propane/rule.rb

@@ -6,6 +6,10 @@ class Propane
     #   Rule components.
     attr_reader :components
 
+    # @return [Hash]
+    #   Field aliases.
+    attr_reader :aliases
+
     # @return [String]
     #   User code associated with the rule.
     attr_reader :code
@@ -49,7 +53,19 @@ class Propane
     #   Line number where the rule was defined in the input grammar.
     def initialize(name, components, code, ptypename, line_number)
       @name = name
-      @components = components
+      @aliases = {}
+      @components = components.each_with_index.map do |component, i|
+        if component =~ /(\S+):(\S+)/
+          c, aliasname = $1, $2
+          if @aliases[aliasname]
+            raise Error.new("Error: duplicate field alias `#{aliasname}` for rule #{name} defined on line #{line_number}")
+          end
+          @aliases[aliasname] = i
+          c
+        else
+          component
+        end
+      end
       @rule_set_node_field_index_map = components.map {0}
       @code = code
       @ptypename = ptypename

lib/propane/rule_set.rb

@@ -100,7 +100,9 @@ class Propane
 
     # Finalize a RuleSet after adding all Rules to it.
     def finalize(grammar)
-      build_ast_fields(grammar)
+      if grammar.ast
+        build_ast_fields(grammar)
+      end
     end
 
     private
@@ -148,6 +150,18 @@ class Propane
             "#{grammar.ast_prefix}#{node_name}#{grammar.ast_suffix}"
         end
       end
+      # Now merge in the field aliases as given by the user in the
+      # grammar.
+      field_aliases = {}
+      @rules.each do |rule|
+        rule.aliases.each do |alias_name, index|
+          if field_aliases[alias_name] && field_aliases[alias_name] != index
+            raise Error.new("Error: conflicting AST node field positions for alias `#{alias_name}`")
+          end
+          field_aliases[alias_name] = index
+          @ast_fields[index][alias_name] = @ast_fields[index].first[1]
+        end
+      end
     end
 
   end

lib/propane/version.rb

@@ -1,3 +1,3 @@
 class Propane
-  VERSION = "1.4.0"
+  VERSION = "1.5.0"
 end

spec/propane_spec.rb

@@ -213,6 +213,42 @@ EOF
     expect(File.binread("spec/run/testparser.log")).to match %r{Shift/Reduce conflict \(state \d+\) between token b and rule As2\? \(defined on line 4\)}
   end
 
+  it "errors on duplicate field aliases in a rule" do
+    write_grammar <<EOF
+token a;
+token b;
+Start -> a:foo b:foo;
+EOF
+    results = run_propane(extra_args: %w[-w], capture: true)
+    expect(results.stderr).to match %r{Error: duplicate field alias `foo` for rule Start defined on line 3}
+    expect(results.status).to_not eq 0
+  end
+
+  it "errors when an alias is in different positions for different rules in a rule set when AST mode is enabled" do
+    write_grammar <<EOF
+ast;
+token a;
+token b;
+Start -> a:foo b;
+Start -> b b:foo;
+EOF
+    results = run_propane(extra_args: %w[-w], capture: true)
+    expect(results.stderr).to match %r{Error: conflicting AST node field positions for alias `foo`}
+    expect(results.status).to_not eq 0
+  end
+
+  it "does not error when an alias is in different positions for different rules in a rule set when AST mode is not enabled" do
+    write_grammar <<EOF
+token a;
+token b;
+Start -> a:foo b;
+Start -> b b:foo;
+EOF
+    results = run_propane(extra_args: %w[-w], capture: true)
+    expect(results.stderr).to eq ""
+    expect(results.status).to eq 0
+  end
+
   %w[d c].each do |language|
 
     context "#{language.upcase} language" do
@@ -1081,17 +1117,17 @@ EOF
         expect(results.status).to eq 0
       end
 
-      it "stores the token position in the AST Token node" do
+      it "stores token and rule positions in AST nodes" do
         write_grammar <<EOF
 ast;
 
 token a;
-token b;
-token c;
+token bb;
+token c /c(.|\\n)*c/;
 drop /\\s+/;
 Start -> T T T;
 T -> a;
-T -> b;
+T -> bb;
 T -> c;
 EOF
         run_propane(language: language)
@@ -1100,6 +1136,90 @@ EOF
         expect(results.stderr).to eq ""
         expect(results.status).to eq 0
       end
+
+      it "stores invalid positions for empty rule matches" do
+        write_grammar <<EOF
+ast;
+
+token a;
+token bb;
+token c /c(.|\\n)*c/;
+drop /\\s+/;
+Start -> T Start;
+Start -> ;
+T -> a A;
+A -> bb? c?;
+EOF
+        run_propane(language: language)
+        compile("spec/test_ast_invalid_positions.#{language}", language: language)
+        results = run_test
+        expect(results.stderr).to eq ""
+        expect(results.status).to eq 0
+      end
+
+      it "allows specifying field aliases in AST mode" do
+        write_grammar <<EOF
+ast;
+
+token a;
+token b;
+token c;
+drop /\\s+/;
+Start -> T:first T:second T:third;
+T -> a;
+T -> b;
+T -> c;
+EOF
+        run_propane(language: language)
+        compile("spec/test_ast_field_aliases.#{language}", language: language)
+        results = run_test
+        expect(results.stderr).to eq ""
+        expect(results.status).to eq 0
+      end
+
+      it "allows specifying field aliases when AST mode is not enabled" do
+        if language == "d"
+          write_grammar <<EOF
+<<
+import std.stdio;
+>>
+ptype string;
+token id /[a-zA-Z_][a-zA-Z0-9_]*/ <<
+  $$ = match;
+>>
+drop /\\s+/;
+Start -> id:first id:second <<
+  writeln("first is ", ${first});
+  writeln("second is ", ${second});
+>>
+EOF
+        else
+          write_grammar <<EOF
+<<
+#include <stdio.h>
+#include <string.h>
+>>
+ptype char const *;
+token id /[a-zA-Z_][a-zA-Z0-9_]*/ <<
+  char * s = malloc(match_length + 1);
+  strncpy(s, (char const *)match, match_length);
+  s[match_length] = 0;
+  $$ = s;
+>>
+drop /\\s+/;
+Start -> id:first id:second <<
+  printf("first is %s\\n", ${first});
+  printf("second is %s\\n", ${second});
+>>
+EOF
+        end
+        run_propane(language: language)
+        compile("spec/test_field_aliases.#{language}", language: language)
+        results = run_test
+        expect(results.stderr).to eq ""
+        expect(results.status).to eq 0
+        expect(results.stdout).to match /first is foo1.*second is bar2/m
+      end
     end
   end
 end

spec/test_ast_field_aliases.c

@@ -0,0 +1,19 @@
+#include "testparser.h"
+#include <assert.h>
+#include <string.h>
+#include "testutils.h"
+
+int main()
+{
+    char const * input = "\na\nb\nc";
+    p_context_t context;
+    p_context_init(&context, (uint8_t const *)input, strlen(input));
+    assert(p_parse(&context) == P_SUCCESS);
+    Start * start = p_result(&context);
+
+    assert_eq(TOKEN_a, start->first->pToken->token);
+    assert_eq(TOKEN_b, start->second->pToken->token);
+    assert_eq(TOKEN_c, start->third->pToken->token);
+
+    return 0;
+}

spec/test_ast_field_aliases.d

@@ -0,0 +1,21 @@
+import testparser;
+import std.stdio;
+import testutils;
+
+int main()
+{
+    return 0;
+}
+
+unittest
+{
+    string input = "\na\nb\nc";
+    p_context_t context;
+    p_context_init(&context, input);
+    assert(p_parse(&context) == P_SUCCESS);
+    Start * start = p_result(&context);
+
+    assert_eq(TOKEN_a, start.first.pToken.token);
+    assert_eq(TOKEN_b, start.second.pToken.token);
+    assert_eq(TOKEN_c, start.third.pToken.token);
+}

spec/test_ast_invalid_positions.c

@@ -0,0 +1,102 @@
+#include "testparser.h"
+#include <assert.h>
+#include <string.h>
+#include "testutils.h"
+
+int main()
+{
+    char const * input = "\na\n  bb ccc";
+    p_context_t context;
+    p_context_init(&context, (uint8_t const *)input, strlen(input));
+    assert(p_parse(&context) == P_SUCCESS);
+    Start * start = p_result(&context);
+
+    assert_eq(1, start->pT1->pToken->position.row);
+    assert_eq(0, start->pT1->pToken->position.col);
+    assert_eq(1, start->pT1->pToken->end_position.row);
+    assert_eq(0, start->pT1->pToken->end_position.col);
+    assert(p_position_valid(start->pT1->pA->position));
+    assert_eq(2, start->pT1->pA->position.row);
+    assert_eq(2, start->pT1->pA->position.col);
+    assert_eq(2, start->pT1->pA->end_position.row);
+    assert_eq(7, start->pT1->pA->end_position.col);
+    assert_eq(1, start->pT1->position.row);
+    assert_eq(0, start->pT1->position.col);
+    assert_eq(2, start->pT1->end_position.row);
+    assert_eq(7, start->pT1->end_position.col);
+
+    assert_eq(1, start->position.row);
+    assert_eq(0, start->position.col);
+    assert_eq(2, start->end_position.row);
+    assert_eq(7, start->end_position.col);
+
+    input = "a\nbb";
+    p_context_init(&context, (uint8_t const *)input, strlen(input));
+    assert(p_parse(&context) == P_SUCCESS);
+    start = p_result(&context);
+
+    assert_eq(0, start->pT1->pToken->position.row);
+    assert_eq(0, start->pT1->pToken->position.col);
+    assert_eq(0, start->pT1->pToken->end_position.row);
+    assert_eq(0, start->pT1->pToken->end_position.col);
+    assert(p_position_valid(start->pT1->pA->position));
+    assert_eq(1, start->pT1->pA->position.row);
+    assert_eq(0, start->pT1->pA->position.col);
+    assert_eq(1, start->pT1->pA->end_position.row);
+    assert_eq(1, start->pT1->pA->end_position.col);
+    assert_eq(0, start->pT1->position.row);
+    assert_eq(0, start->pT1->position.col);
+    assert_eq(1, start->pT1->end_position.row);
+    assert_eq(1, start->pT1->end_position.col);
+
+    assert_eq(0, start->position.row);
+    assert_eq(0, start->position.col);
+    assert_eq(1, start->end_position.row);
+    assert_eq(1, start->end_position.col);
+
+    input = "a\nc\nc";
+    p_context_init(&context, (uint8_t const *)input, strlen(input));
+    assert(p_parse(&context) == P_SUCCESS);
+    start = p_result(&context);
+
+    assert_eq(0, start->pT1->pToken->position.row);
+    assert_eq(0, start->pT1->pToken->position.col);
+    assert_eq(0, start->pT1->pToken->end_position.row);
+    assert_eq(0, start->pT1->pToken->end_position.col);
+    assert(p_position_valid(start->pT1->pA->position));
+    assert_eq(1, start->pT1->pA->position.row);
+    assert_eq(0, start->pT1->pA->position.col);
+    assert_eq(2, start->pT1->pA->end_position.row);
+    assert_eq(0, start->pT1->pA->end_position.col);
+    assert_eq(0, start->pT1->position.row);
+    assert_eq(0, start->pT1->position.col);
+    assert_eq(2, start->pT1->end_position.row);
+    assert_eq(0, start->pT1->end_position.col);
+
+    assert_eq(0, start->position.row);
+    assert_eq(0, start->position.col);
+    assert_eq(2, start->end_position.row);
+    assert_eq(0, start->end_position.col);
+
+    input = "a";
+    p_context_init(&context, (uint8_t const *)input, strlen(input));
+    assert(p_parse(&context) == P_SUCCESS);
+    start = p_result(&context);
+
+    assert_eq(0, start->pT1->pToken->position.row);
+    assert_eq(0, start->pT1->pToken->position.col);
+    assert_eq(0, start->pT1->pToken->end_position.row);
+    assert_eq(0, start->pT1->pToken->end_position.col);
+    assert(!p_position_valid(start->pT1->pA->position));
+    assert_eq(0, start->pT1->position.row);
+    assert_eq(0, start->pT1->position.col);
+    assert_eq(0, start->pT1->end_position.row);
+    assert_eq(0, start->pT1->end_position.col);
+
+    assert_eq(0, start->position.row);
+    assert_eq(0, start->position.col);
+    assert_eq(0, start->end_position.row);
+    assert_eq(0, start->end_position.col);
+
+    return 0;
+}

spec/test_ast_invalid_positions.d

@@ -0,0 +1,104 @@
+import testparser;
+import std.stdio;
+import testutils;
+
+int main()
+{
+    return 0;
+}
+
+unittest
+{
+    string input = "\na\n  bb ccc";
+    p_context_t context;
+    p_context_init(&context, input);
+    assert(p_parse(&context) == P_SUCCESS);
+    Start * start = p_result(&context);
+
+    assert_eq(1, start.pT1.pToken.position.row);
+    assert_eq(0, start.pT1.pToken.position.col);
+    assert_eq(1, start.pT1.pToken.end_position.row);
+    assert_eq(0, start.pT1.pToken.end_position.col);
+    assert(start.pT1.pA.position.valid);
+    assert_eq(2, start.pT1.pA.position.row);
+    assert_eq(2, start.pT1.pA.position.col);
+    assert_eq(2, start.pT1.pA.end_position.row);
+    assert_eq(7, start.pT1.pA.end_position.col);
+    assert_eq(1, start.pT1.position.row);
+    assert_eq(0, start.pT1.position.col);
+    assert_eq(2, start.pT1.end_position.row);
+    assert_eq(7, start.pT1.end_position.col);
+
+    assert_eq(1, start.position.row);
+    assert_eq(0, start.position.col);
+    assert_eq(2, start.end_position.row);
+    assert_eq(7, start.end_position.col);
+
+    input = "a\nbb";
+    p_context_init(&context, input);
+    assert(p_parse(&context) == P_SUCCESS);
+    start = p_result(&context);
+
+    assert_eq(0, start.pT1.pToken.position.row);
+    assert_eq(0, start.pT1.pToken.position.col);
+    assert_eq(0, start.pT1.pToken.end_position.row);
+    assert_eq(0, start.pT1.pToken.end_position.col);
+    assert(start.pT1.pA.position.valid);
+    assert_eq(1, start.pT1.pA.position.row);
+    assert_eq(0, start.pT1.pA.position.col);
+    assert_eq(1, start.pT1.pA.end_position.row);
+    assert_eq(1, start.pT1.pA.end_position.col);
+    assert_eq(0, start.pT1.position.row);
+    assert_eq(0, start.pT1.position.col);
+    assert_eq(1, start.pT1.end_position.row);
+    assert_eq(1, start.pT1.end_position.col);
+
+    assert_eq(0, start.position.row);
+    assert_eq(0, start.position.col);
+    assert_eq(1, start.end_position.row);
+    assert_eq(1, start.end_position.col);
+
+    input = "a\nc\nc";
+    p_context_init(&context, input);
+    assert(p_parse(&context) == P_SUCCESS);
+    start = p_result(&context);
+
+    assert_eq(0, start.pT1.pToken.position.row);
+    assert_eq(0, start.pT1.pToken.position.col);
+    assert_eq(0, start.pT1.pToken.end_position.row);
+    assert_eq(0, start.pT1.pToken.end_position.col);
+    assert(start.pT1.pA.position.valid);
+    assert_eq(1, start.pT1.pA.position.row);
+    assert_eq(0, start.pT1.pA.position.col);
+    assert_eq(2, start.pT1.pA.end_position.row);
+    assert_eq(0, start.pT1.pA.end_position.col);
+    assert_eq(0, start.pT1.position.row);
+    assert_eq(0, start.pT1.position.col);
+    assert_eq(2, start.pT1.end_position.row);
+    assert_eq(0, start.pT1.end_position.col);
+
+    assert_eq(0, start.position.row);
+    assert_eq(0, start.position.col);
+    assert_eq(2, start.end_position.row);
+    assert_eq(0, start.end_position.col);
+
+    input = "a";
+    p_context_init(&context, input);
+    assert(p_parse(&context) == P_SUCCESS);
+    start = p_result(&context);
+
+    assert_eq(0, start.pT1.pToken.position.row);
+    assert_eq(0, start.pT1.pToken.position.col);
+    assert_eq(0, start.pT1.pToken.end_position.row);
+    assert_eq(0, start.pT1.pToken.end_position.col);
+    assert(!start.pT1.pA.position.valid);
+    assert_eq(0, start.pT1.position.row);
+    assert_eq(0, start.pT1.position.col);
+    assert_eq(0, start.pT1.end_position.row);
+    assert_eq(0, start.pT1.end_position.col);
+
+    assert_eq(0, start.position.row);
+    assert_eq(0, start.position.col);
+    assert_eq(0, start.end_position.row);
+    assert_eq(0, start.end_position.col);
+}

spec/test_ast_token_positions.c

@@ -5,29 +5,80 @@
 
 int main()
 {
-    char const * input = "abc";
+    char const * input = "abbccc";
     p_context_t context;
     p_context_init(&context, (uint8_t const *)input, strlen(input));
     assert(p_parse(&context) == P_SUCCESS);
     Start * start = p_result(&context);
+
     assert_eq(0, start->pT1->pToken->position.row);
     assert_eq(0, start->pT1->pToken->position.col);
+    assert_eq(0, start->pT1->pToken->end_position.row);
+    assert_eq(0, start->pT1->pToken->end_position.col);
+    assert_eq(0, start->pT1->position.row);
+    assert_eq(0, start->pT1->position.col);
+    assert_eq(0, start->pT1->end_position.row);
+    assert_eq(0, start->pT1->end_position.col);
+
     assert_eq(0, start->pT2->pToken->position.row);
     assert_eq(1, start->pT2->pToken->position.col);
-    assert_eq(0, start->pT3->pToken->position.row);
-    assert_eq(2, start->pT3->pToken->position.col);
+    assert_eq(0, start->pT2->pToken->end_position.row);
+    assert_eq(2, start->pT2->pToken->end_position.col);
+    assert_eq(0, start->pT2->position.row);
+    assert_eq(1, start->pT2->position.col);
+    assert_eq(0, start->pT2->end_position.row);
+    assert_eq(2, start->pT2->end_position.col);
 
-    input = "\n\n  a\nc\n\n     a";
+    assert_eq(0, start->pT3->pToken->position.row);
+    assert_eq(3, start->pT3->pToken->position.col);
+    assert_eq(0, start->pT3->pToken->end_position.row);
+    assert_eq(5, start->pT3->pToken->end_position.col);
+    assert_eq(0, start->pT3->position.row);
+    assert_eq(3, start->pT3->position.col);
+    assert_eq(0, start->pT3->end_position.row);
+    assert_eq(5, start->pT3->end_position.col);
+
+    assert_eq(0, start->position.row);
+    assert_eq(0, start->position.col);
+    assert_eq(0, start->end_position.row);
+    assert_eq(5, start->end_position.col);
+
+    input = "\n\n  bb\nc\ncc\n\n     a";
     p_context_init(&context, (uint8_t const *)input, strlen(input));
     assert(p_parse(&context) == P_SUCCESS);
     start = p_result(&context);
+
     assert_eq(2, start->pT1->pToken->position.row);
     assert_eq(2, start->pT1->pToken->position.col);
+    assert_eq(2, start->pT1->pToken->end_position.row);
+    assert_eq(3, start->pT1->pToken->end_position.col);
+    assert_eq(2, start->pT1->position.row);
+    assert_eq(2, start->pT1->position.col);
+    assert_eq(2, start->pT1->end_position.row);
+    assert_eq(3, start->pT1->end_position.col);
+
     assert_eq(3, start->pT2->pToken->position.row);
     assert_eq(0, start->pT2->pToken->position.col);
-    assert_eq(5, start->pT3->pToken->position.row);
+    assert_eq(4, start->pT2->pToken->end_position.row);
+    assert_eq(1, start->pT2->pToken->end_position.col);
+    assert_eq(3, start->pT2->position.row);
+    assert_eq(0, start->pT2->position.col);
+    assert_eq(4, start->pT2->end_position.row);
+    assert_eq(1, start->pT2->end_position.col);
+
+    assert_eq(6, start->pT3->pToken->position.row);
     assert_eq(5, start->pT3->pToken->position.col);
+    assert_eq(6, start->pT3->pToken->end_position.row);
+    assert_eq(5, start->pT3->pToken->end_position.col);
+    assert_eq(6, start->pT3->position.row);
+    assert_eq(5, start->pT3->position.col);
+    assert_eq(6, start->pT3->end_position.row);
+    assert_eq(5, start->pT3->end_position.col);
+
+    assert_eq(2, start->position.row);
+    assert_eq(2, start->position.col);
+    assert_eq(6, start->end_position.row);
+    assert_eq(5, start->end_position.col);
 
     return 0;
 }
-

spec/test_ast_token_positions.d

@@ -9,26 +9,78 @@ int main()
 
 unittest
 {
-    string input = "abc";
+    string input = "abbccc";
     p_context_t context;
     p_context_init(&context, input);
     assert(p_parse(&context) == P_SUCCESS);
     Start * start = p_result(&context);
+
     assert_eq(0, start.pT1.pToken.position.row);
     assert_eq(0, start.pT1.pToken.position.col);
+    assert_eq(0, start.pT1.pToken.end_position.row);
+    assert_eq(0, start.pT1.pToken.end_position.col);
+    assert_eq(0, start.pT1.position.row);
+    assert_eq(0, start.pT1.position.col);
+    assert_eq(0, start.pT1.end_position.row);
+    assert_eq(0, start.pT1.end_position.col);
+
     assert_eq(0, start.pT2.pToken.position.row);
     assert_eq(1, start.pT2.pToken.position.col);
-    assert_eq(0, start.pT3.pToken.position.row);
-    assert_eq(2, start.pT3.pToken.position.col);
+    assert_eq(0, start.pT2.pToken.end_position.row);
+    assert_eq(2, start.pT2.pToken.end_position.col);
+    assert_eq(0, start.pT2.position.row);
+    assert_eq(1, start.pT2.position.col);
+    assert_eq(0, start.pT2.end_position.row);
+    assert_eq(2, start.pT2.end_position.col);
 
-    input = "\n\n  a\nc\n\n     a";
+    assert_eq(0, start.pT3.pToken.position.row);
+    assert_eq(3, start.pT3.pToken.position.col);
+    assert_eq(0, start.pT3.pToken.end_position.row);
+    assert_eq(5, start.pT3.pToken.end_position.col);
+    assert_eq(0, start.pT3.position.row);
+    assert_eq(3, start.pT3.position.col);
+    assert_eq(0, start.pT3.end_position.row);
+    assert_eq(5, start.pT3.end_position.col);
+
+    assert_eq(0, start.position.row);
+    assert_eq(0, start.position.col);
+    assert_eq(0, start.end_position.row);
+    assert_eq(5, start.end_position.col);
+
+    input = "\n\n  bb\nc\ncc\n\n     a";
     p_context_init(&context, input);
     assert(p_parse(&context) == P_SUCCESS);
     start = p_result(&context);
+
     assert_eq(2, start.pT1.pToken.position.row);
     assert_eq(2, start.pT1.pToken.position.col);
+    assert_eq(2, start.pT1.pToken.end_position.row);
+    assert_eq(3, start.pT1.pToken.end_position.col);
+    assert_eq(2, start.pT1.position.row);
+    assert_eq(2, start.pT1.position.col);
+    assert_eq(2, start.pT1.end_position.row);
+    assert_eq(3, start.pT1.end_position.col);
+
     assert_eq(3, start.pT2.pToken.position.row);
     assert_eq(0, start.pT2.pToken.position.col);
-    assert_eq(5, start.pT3.pToken.position.row);
+    assert_eq(4, start.pT2.pToken.end_position.row);
+    assert_eq(1, start.pT2.pToken.end_position.col);
+    assert_eq(3, start.pT2.position.row);
+    assert_eq(0, start.pT2.position.col);
+    assert_eq(4, start.pT2.end_position.row);
+    assert_eq(1, start.pT2.end_position.col);
+
+    assert_eq(6, start.pT3.pToken.position.row);
     assert_eq(5, start.pT3.pToken.position.col);
+    assert_eq(6, start.pT3.pToken.end_position.row);
+    assert_eq(5, start.pT3.pToken.end_position.col);
+    assert_eq(6, start.pT3.position.row);
+    assert_eq(5, start.pT3.position.col);
+    assert_eq(6, start.pT3.end_position.row);
+    assert_eq(5, start.pT3.end_position.col);
+
+    assert_eq(2, start.position.row);
+    assert_eq(2, start.position.col);
+    assert_eq(6, start.end_position.row);
+    assert_eq(5, start.end_position.col);
 }

spec/test_field_aliases.c

@@ -0,0 +1,13 @@
+#include "testparser.h"
+#include <assert.h>
+#include <string.h>
+#include "testutils.h"
+
+int main()
+{
+    char const * input = "foo1\nbar2";
+    p_context_t context;
+    p_context_init(&context, (uint8_t const *)input, strlen(input));
+    assert(p_parse(&context) == P_SUCCESS);
+    return 0;
+}

spec/test_field_aliases.d

@@ -0,0 +1,15 @@
+import testparser;
+import std.stdio;
+
+int main()
+{
+    return 0;
+}
+
+unittest
+{
+    string input = "foo1\nbar2";
+    p_context_t context;
+    p_context_init(&context, input);
+    assert(p_parse(&context) == P_SUCCESS);
+}

spec/test_lexer.c

@@ -43,41 +43,57 @@ int main()
     assert(p_lex(&context, &token_info) == P_SUCCESS);
     assert(token_info.position.row == 0u);
     assert(token_info.position.col == 0u);
+    assert(token_info.end_position.row == 0u);
+    assert(token_info.end_position.col == 0u);
     assert(token_info.length == 1u);
     assert(token_info.token == TOKEN_int);
     assert(p_lex(&context, &token_info) == P_SUCCESS);
     assert(token_info.position.row == 0u);
     assert(token_info.position.col == 2u);
+    assert(token_info.end_position.row == 0u);
+    assert(token_info.end_position.col == 2u);
     assert(token_info.length == 1u);
     assert(token_info.token == TOKEN_plus);
     assert(p_lex(&context, &token_info) == P_SUCCESS);
     assert(token_info.position.row == 0u);
     assert(token_info.position.col == 4u);
+    assert(token_info.end_position.row == 0u);
+    assert(token_info.end_position.col == 4u);
     assert(token_info.length == 1u);
     assert(token_info.token == TOKEN_int);
     assert(p_lex(&context, &token_info) == P_SUCCESS);
     assert(token_info.position.row == 0u);
     assert(token_info.position.col == 6u);
+    assert(token_info.end_position.row == 0u);
+    assert(token_info.end_position.col == 6u);
     assert(token_info.length == 1u);
     assert(token_info.token == TOKEN_times);
     assert(p_lex(&context, &token_info) == P_SUCCESS);
     assert(token_info.position.row == 1u);
     assert(token_info.position.col == 0u);
+    assert(token_info.end_position.row == 1u);
+    assert(token_info.end_position.col == 2u);
     assert(token_info.length == 3u);
     assert(token_info.token == TOKEN_int);
     assert(p_lex(&context, &token_info) == P_SUCCESS);
     assert(token_info.position.row == 1u);
     assert(token_info.position.col == 4u);
+    assert(token_info.end_position.row == 1u);
+    assert(token_info.end_position.col == 4u);
     assert(token_info.length == 1u);
     assert(token_info.token == TOKEN_plus);
     assert(p_lex(&context, &token_info) == P_SUCCESS);
     assert(token_info.position.row == 1u);
     assert(token_info.position.col == 6u);
+    assert(token_info.end_position.row == 1u);
+    assert(token_info.end_position.col == 8u);
     assert(token_info.length == 3u);
     assert(token_info.token == TOKEN_int);
     assert(p_lex(&context, &token_info) == P_SUCCESS);
     assert(token_info.position.row == 1u);
     assert(token_info.position.col == 9u);
+    assert(token_info.end_position.row == 1u);
+    assert(token_info.end_position.col == 9u);
     assert(token_info.length == 0u);
     assert(token_info.token == TOKEN___EOF);
 
@@ -85,6 +101,8 @@ int main()
     assert(p_lex(&context, &token_info) == P_SUCCESS);
     assert(token_info.position.row == 0u);
     assert(token_info.position.col == 0u);
+    assert(token_info.end_position.row == 0u);
+    assert(token_info.end_position.col == 0u);
     assert(token_info.length == 0u);
     assert(token_info.token == TOKEN___EOF);
 

spec/test_lexer.d

@@ -47,23 +47,23 @@ unittest
     p_context_t context;
     p_context_init(&context, input);
     assert(p_lex(&context, &token_info) == P_SUCCESS);
-    assert(token_info == p_token_info_t(p_position_t(0, 0), 1, TOKEN_int));
+    assert(token_info == p_token_info_t(p_position_t(0, 0), p_position_t(0, 0), 1, TOKEN_int));
     assert(p_lex(&context, &token_info) == P_SUCCESS);
-    assert(token_info == p_token_info_t(p_position_t(0, 2), 1, TOKEN_plus));
+    assert(token_info == p_token_info_t(p_position_t(0, 2), p_position_t(0, 2), 1, TOKEN_plus));
     assert(p_lex(&context, &token_info) == P_SUCCESS);
-    assert(token_info == p_token_info_t(p_position_t(0, 4), 1, TOKEN_int));
+    assert(token_info == p_token_info_t(p_position_t(0, 4), p_position_t(0, 4), 1, TOKEN_int));
     assert(p_lex(&context, &token_info) == P_SUCCESS);
-    assert(token_info == p_token_info_t(p_position_t(0, 6), 1, TOKEN_times));
+    assert(token_info == p_token_info_t(p_position_t(0, 6), p_position_t(0, 6), 1, TOKEN_times));
     assert(p_lex(&context, &token_info) == P_SUCCESS);
-    assert(token_info == p_token_info_t(p_position_t(1, 0), 3, TOKEN_int));
+    assert(token_info == p_token_info_t(p_position_t(1, 0), p_position_t(1, 2), 3, TOKEN_int));
     assert(p_lex(&context, &token_info) == P_SUCCESS);
-    assert(token_info == p_token_info_t(p_position_t(1, 4), 1, TOKEN_plus));
+    assert(token_info == p_token_info_t(p_position_t(1, 4), p_position_t(1, 4), 1, TOKEN_plus));
     assert(p_lex(&context, &token_info) == P_SUCCESS);
-    assert(token_info == p_token_info_t(p_position_t(1, 6), 3, TOKEN_int));
+    assert(token_info == p_token_info_t(p_position_t(1, 6), p_position_t(1, 8), 3, TOKEN_int));
     assert(p_lex(&context, &token_info) == P_SUCCESS);
-    assert(token_info == p_token_info_t(p_position_t(1, 9), 0, TOKEN___EOF));
+    assert(token_info == p_token_info_t(p_position_t(1, 9), p_position_t(1, 9), 0, TOKEN___EOF));
 
     p_context_init(&context, "");
     assert(p_lex(&context, &token_info) == P_SUCCESS);
-    assert(token_info == p_token_info_t(p_position_t(0, 0), 0, TOKEN___EOF));
+    assert(token_info == p_token_info_t(p_position_t(0, 0), p_position_t(0, 0), 0, TOKEN___EOF));
 }