josh/propane
1
0
Fork 0
Code Issues 3 Pull Requests Projects Releases Wiki Activity

Convert Decoder.decode_code_point return type to a SumType

Browse Source
This commit is contained in:
Josh Holtrop 2023-06-29 19:21:30 -04:00
parent 9895733a05
commit d466189982
1 changed files with 65 additions and 101 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

76
assets/parser.d.erb
View File

@ -2,8 +2,8 @@
module <%= @grammar.modulename %>; module <%= @grammar.modulename %>;
<% end %> <% end %>
import std.stdio; import std.stdio;
import std.sumtype;
<% @grammar.code_blocks.each do |code| %> <% @grammar.code_blocks.each do |code| %>
<%= code %> <%= code %>
@ -71,54 +71,23 @@ class <%= @classname %>
static class Decoder static class Decoder
{ {
struct Result struct Success
{ {
enum Type
{
SUCCESS,
EOF,
DECODE_ERROR,
}
private Type type;
CodePoint code_point; CodePoint code_point;
uint code_point_length; uint code_point_length;
static Result success(CodePoint code_point, uint code_point_length)
{
return Result(Type.SUCCESS, code_point, code_point_length);
} }
struct EOF {}
struct DecodeError {}
bool is_success() static SumType!(
{ Success,
return type == Type.SUCCESS; EOF,
} DecodeError)
decode_code_point(string input)
static Result eof()
{
return Result(Type.EOF);
}
bool is_eof()
{
return type == Type.EOF;
}
static Result decode_error()
{
return Result(Type.DECODE_ERROR);
}
bool is_decode_error()
{
return type == Type.DECODE_ERROR;
}
}
static Result decode_code_point(string input)
{ {
if (input.length == 0u) if (input.length == 0u)
{ {
return Result.eof(); return cast(ReturnType!decode_code_point)EOF();
} }
char c = input[0]; char c = input[0];
CodePoint code_point; CodePoint code_point;
@ -158,11 +127,11 @@ class <%= @classname %>
} }
else else
{ {
return Result.decode_error(); return cast(ReturnType!decode_code_point)DecodeError();
} }
if (input.length <= following_bytes) if (input.length <= following_bytes)
{ {
return Result.decode_error(); return cast(ReturnType!decode_code_point)DecodeError();
} }
code_point_length = following_bytes + 1u; code_point_length = following_bytes + 1u;
for (size_t i = 0u; i < following_bytes; i++) for (size_t i = 0u; i < following_bytes; i++)
@ -170,12 +139,12 @@ class <%= @classname %>
char b = input[i + 1u]; char b = input[i + 1u];
if ((b & 0xC0u) != 0x80u) if ((b & 0xC0u) != 0x80u)
{ {
return Result.decode_error(); return cast(ReturnType!decode_code_point)DecodeError();
} }
code_point = (code_point << 6u) | (b & 0x3Fu); code_point = (code_point << 6u) | (b & 0x3Fu);
} }
} }
return Result.success(code_point, code_point_length); return cast(ReturnType!decode_code_point)Success(code_point, code_point_length);
} }
} }
@ -498,14 +467,10 @@ class <%= @classname %>
uint current_state = modes[m_mode].state_table_offset; uint current_state = modes[m_mode].state_table_offset;
for (;;) for (;;)
{ {
auto decoded = Decoder.decode_code_point(m_input[(m_input_position + attempt_match.length)..(m_input.length)]);
if (decoded.is_decode_error())
{
return FindLongestMatchResult.decode_error();
}
bool lex_continue = false; bool lex_continue = false;
if (decoded.is_eof()) Decoder.decode_code_point(m_input[(m_input_position + attempt_match.length)..(m_input.length)]).match!(
{ (Decoder.DecodeError de) {return FindLongestMatchResult.decode_error();},
(Decoder.EOF e) {
/* We hit EOF. */ /* We hit EOF. */
if (longest_match.length > 0) if (longest_match.length > 0)
{ {
@ -522,9 +487,8 @@ class <%= @classname %>
/* Valid EOF return. */ /* Valid EOF return. */
return FindLongestMatchResult.eof(); return FindLongestMatchResult.eof();
} }
} },
else (Decoder.Success decoded) {
{
auto transition_result = transition(current_state, decoded.code_point); auto transition_result = transition(current_state, decoded.code_point);
if (transition_result.found()) if (transition_result.found())
{ {
@ -554,7 +518,7 @@ class <%= @classname %>
{ {
return FindLongestMatchResult.unexpected_input(attempt_match.length + decoded.code_point_length); return FindLongestMatchResult.unexpected_input(attempt_match.length + decoded.code_point_length);
} }
} });
} }
} }