From: Sonja Elen Kisa <sonja@...>
Date: 2009-12-18T12:21:49+09:00
Subject: Re: how to alias keywords?

From #ruby-lang on Freenode IRC tonight:

[21:44] <manveru> Sonja: 
http://github.com/shyouhei/ruby/blob/trunk/parse.y#L10106-10154
[21:44] <argv[0]> right. you either get "if" or you get "somethingelse", 
but not both
[21:45] <zenspider> if you want both, you'll have to declare both 
english and otherlanguage as keywords and then modify the grammar 
productions to accept both
[21:46] <argv[0]> yea, that.
[21:46] <argv[0]> which is not quite as easy
[21:46] <zenspider> essentially: if expr then? expr => (if|fi) expr 
(then|neht)?
[21:46] <zenspider> just a bit tedious considering how f'd up the yacc 
file is
[21:47] <zenspider> but start with something that isn't replicated in C 
like class or module
[21:47] <zenspider> experiment with that one change
[21:47] <zenspider> and then expand
[21:48] <zenspider> should all just be algebraic changes, substitute A|B 
for all A
[21:50] <zenspider> looks like the 1.9 (trunk) version is very cleaned 
up... keyword_elsif... very easy to track down all versions then
[21:51] <zenspider> yacc kinda sucks... but we're stuck with it 
(*cough*for now*cough*)
[21:52] <zenspider> my algebraic statement above isn't quite that easy 
since yacc doesn't support EBNF productions cleanly... but you'll get it
[22:06] <argv[0]> Sonja this is about as good as it gets without messing 
with parse.y http://gist.github.com/259256
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