From: Michael Edgar <michael.j.edgar@...>
Date: 2011-06-27T11:31:13+09:00
Subject: [ruby-core:37554] [Ruby 1.9 - Bug #4935] Quoted Label Form for 1.9 Hashes


Issue #4935 has been updated by Michael Edgar.

File label_test.diff added

Sorry, meant to list this as a feature. Test attached.
----------------------------------------
Bug #4935: Quoted Label Form for 1.9 Hashes
http://redmine.ruby-lang.org/issues/4935

Author: Michael Edgar
Status: Open
Priority: Normal
Assignee: 
Category: 
Target version: 
ruby -v: ruby 1.9.3dev (2011-06-27 trunk 32242) [x86_64-darwin10.7.0]


As discussed in the "Shorthand Hash Syntax for Strings" thread/feature request, several (including Matz) expressed interest in a parallel quoted form for the 1.9 label syntax:

  { foo: bar }
  { 'only-19': true }
  
  x = "hello"
  { "#{x}-world": Date.now }

This personally has come up for me with the new syntax: especially when dealing with command-line options, which often use hyphens, the quoted symbol form is necessary. Not being able to use the new syntax results in funny-looking hashes:

  { foo: bar, baz: qux, :'abc-def' => 1 }

I've attached a patch implementing this change. It allows a colon to follow single-quoted or double-quoted string literals to form a symbol key much like the label syntax introduced in 1.9. The examples listed at the start of this post all work fine. It introduces a new token - tLABEL_END - which replaces tSTRING_END when closing a symbol-label-literal. It introduces a single new grammar production for assoc, which is nearly purely syntactic sugar for the dsym grammar production; I've extracted dsym's implementation to a separate helper function, which is called from the dsym production and from the new label-style production.

I will immediately attach a new passing test for test_hash.rb in a followup post, once this has a feature # and ruby-core thread assigned to it.

NB: By removing the quote check on line 6580, one can make this feature work with any string literal (like "{ %q/foo-bar/: baz}", obviously doesn't work with heredocs) - I personally find this to be silly and inconsistent with the existing symbol syntax. Though it was fun to play with for a bit.


-- 
http://redmine.ruby-lang.org