From: "Eregon (Benoit Daloze)" Date: 2013-10-24T17:24:43+09:00 Subject: [ruby-core:58015] [ruby-trunk - Feature #9049] Shorthands (a:b, *) for inclusive indexing Issue #9049 has been updated by Eregon (Benoit Daloze). I am not sure m[1:3,2:4] is really preferable to m[1..3,2..4] in Ruby. The first one is certainly more Matlab, Octave and Python-like but not Ruby-like to my taste. @david_macmahon What about (1..5).step(2).to_a ? ---------------------------------------- Feature #9049: Shorthands (a:b, *) for inclusive indexing https://bugs.ruby-lang.org/issues/9049#change-42596 Author: mohawkjohn (John Woods) Status: Open Priority: Low Assignee: Category: core Target version: =begin For NMatrix, we've implemented a range shorthand which relies on Hashes: (({m[1=>3,2=>4]})), for example, which returns rows 1 through 3 inclusive of columns 2 through 4 (also inclusive). The original goal was to be able to do (({m[1:3,2:4]})) using the new hash notation, but the new hash notation requires that the key be a symbol ��� it won't accept an integer. Whether through the hash interface or not, it'd be lovely if there were a shorthand for slicing matrices (and even Ruby Arrays) using colon. This could just be an alternate syntax for ranges, also ��� which might make more sense. The other related shorthand we'd love to find a way to implement is the all-inclusive shorthand. It gets to be a pain to type (({n[0...n.shape[0],1...3]})) to get a submatrix (a slice), and it's really difficult to read. As a work-around, we currently use the (({:*})) symbol: (({n[:*,1...3]})). But it'd be simpler if there were a way to use a splat operator without an operand as a function argument. It might be a special case where the (({*})) is treated as a (({:*})) automatically. But this edge case might cause confusion with error messages when users make syntax errors elsewhere. The colon shorthand is the highest priority for us. =end -- http://bugs.ruby-lang.org/