Fix user guide examples for task dependencies

doc/user_guide.md

@@ -265,21 +265,17 @@ which they were added.
 Example:
 
 ```ruby
-task "build" do
-  env do |env|
-    env.Program("^^/proj.elf", glob("src/**/*.c"))
-  end
+proj_env = env do |env|
+  env.Program("^/proj.elf", glob("src/**/*.c"))
 end
 
-task "flash", deps: "build" do
-  sh "nrfjprog", "-f", "NRF52", "--program", env.expand("^^/proj.elf")
+task "flash" do
+  sh "nrfjprog", "-f", "NRF52", "--program", proj_env.expand("^/proj.elf")
 end
 ```
 
-In this example, the `flash` task depends on the `build` task.
-So if the project had not yet been built, and the user executes
-`./rscons flash`, the project would first be built and then flashed to the
-target.
+In this example, the `flash` task would first build the proj.elf target and
+then flash it to target with the nrfjprog program.
 
 If the `task` method is called again with the name of an already existing task,
 the task is not overwritten, but rather modified.
@@ -287,6 +283,34 @@ Any newly specified dependencies are added to the current dependencies.
 Any action block is appended to the task's list of action blocks to execute
 when the task is executed.
 
+For example, with the `Rsconscript`:
+
+```ruby
+task "a" do
+  puts "A"
+end
+
+task "b" do
+  puts "B"
+end
+
+task "c", depends: "a" do
+  puts "C1"
+end
+
+task "c", depends: "b" do
+  puts "C2"
+end
+```
+
+The following behavior is observed:
+
+    $ ./rscons c
+    A
+    B
+    C1
+    C2
+
 Note that for a simple project, the build script may not need to define any
 tasks at all and could just make use of the Rscons built-in default task (see
 ${#Default Task}).
@@ -378,7 +402,7 @@ argument (task name) automatically filled in by the shortcut method.
 For example:
 
 ```ruby
-default deps: "unpack_compiler" do
+default depends: "unpack_compiler" do
   puts "default task"
 end
 ```
@@ -386,7 +410,7 @@ end
 is equivalent to:
 
 ```ruby
-task "default", deps: "unpack_compiler" do
+task "default", depends: "unpack_compiler" do
   puts "default task"
 end
 ```
@@ -463,11 +487,11 @@ task "build" do
   ...
 end
 
-task "flash" do
+task "flash", depends: "build" do
   ...
 end
 
-default deps: "build"
+default depends: "build"
 ```
 
 Then when the user runs `./rscons` the "build" task will be executed.