From: Josh Cheek <josh.cheek@...>
Date: 2013-01-08T12:46:12+09:00
Subject: How to identify whether a line of code will return?

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Hi, I want to be able to identify whether a line of code will return,
because I want to modify it to capture it's return value. If it returns,
this results in a syntax error:

$ echo 'def m() a = return end' | ruby -c
-:1: void value expression

$ echo $?
1


Here are some tests:
https://github.com/JoshCheek/seeing_is_believing/blob/54f4044e1c858777f8b0beb690b9dafa9d497106/spec/syntax_analyzer_spec.rb#L114-126

Here is what I tried (hooking into `on_kw "return"` callback in Ripper):
https://github.com/JoshCheek/seeing_is_believing/blob/54f4044e1c858777f8b0beb690b9dafa9d497106/lib/seeing_is_believing/syntax_analyzer.rb#L123-138

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Hi, I want to be able to identify whether a line of code will return, becau=
se I want to modify it to capture it&#39;s return value. If it returns, thi=
s results in a syntax error:<div><br></div><div><div><div>$ echo &#39;def m=
() a =3D return end&#39; | ruby -c</div>
<div>-:1: void value expression</div></div></div><div><br></div><div><div>$=
 echo $?</div><div>1</div></div><div><br></div><div><br></div><div>Here are=
 some tests:</div><div><a href=3D"https://github.com/JoshCheek/seeing_is_be=
lieving/blob/54f4044e1c858777f8b0beb690b9dafa9d497106/spec/syntax_analyzer_=
spec.rb#L114-126">https://github.com/JoshCheek/seeing_is_believing/blob/54f=
4044e1c858777f8b0beb690b9dafa9d497106/spec/syntax_analyzer_spec.rb#L114-126=
</a></div>
<div><br></div><div>Here is what I tried (hooking into `on_kw &quot;return&=
quot;` callback in Ripper):</div><div><a href=3D"https://github.com/JoshChe=
ek/seeing_is_believing/blob/54f4044e1c858777f8b0beb690b9dafa9d497106/lib/se=
eing_is_believing/syntax_analyzer.rb#L123-138">https://github.com/JoshCheek=
/seeing_is_believing/blob/54f4044e1c858777f8b0beb690b9dafa9d497106/lib/seei=
ng_is_believing/syntax_analyzer.rb#L123-138</a></div>

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