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ifelse 0.6.0

IfElse is an implementation of the pure object-oriented conditional syntax found in languages of the SmallTalk family, including Self. Those languages distinguish themselves by taking the "everything is an object / everything is a method" approach to a further extreme than Ruby, and getting rid of almost all cases of special syntax other than object definition and method call. Ruby, of course, already works this way for some purposes -- thus most Ruby developers prefer to write [1, 17, 39].each {|x| puts x} rather than for x in [1, 17, 39] puts x end and 3.times {|n| puts n} instead of i = 1 while i <= 3 puts i i += 1 end This module extends that same preference to conditional statements, providing replacements for the Ruby keywords +if+, and +unless+: x = 1 (x >= 0).if {puts 'positive'} (x < 0).unless {puts 'positive'} Note that as with the built-in special forms these methods replace, these methods are available on any Ruby Object, and obey the usual rules of which values are considered "Truthy" and "Falsey". <b>Note that the primary purpose of this gem is to demonstrate that the built-in (special form) versions of conditionals provided with Ruby are mostly syntactic sugar -- as with the +for+ keyword, there is no real need for these to be built into the language. With that said, the gem is fully tested, has no particular performance penalty (beyond the usual cost of method dispatch), and should be fully useable in general purpose code.</b> <b>Note also that while Smalltalk-family languages also provide an equivalent to the Ruby +else+ keyword, this depends on the more general block/lambda capability of those languages, which allow a method to take multiple blocks as arguments. This could be imitated with a syntax like:</b> # NOT A REAL EXAMPLE (x > 42).if then: lambda {|x| :big }, else: lambda {|x| :small} <b>which is true to the SmallTalk original, but feels less Ruby-ish to me, so I didn't implement this -- perhaps in a later version.</b>

Gemfile:
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installation:
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Versions:

  1. 0.6.0 December 17, 2013 (9 ko)

Dépendances de Development (2):

hoe ~> 3.7
rdoc ~> 4.0

Propriétaires:

Auteurs:

  • Jim Wise

Total de contrôle SHA 256:

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Total de téléchargements 3 729

Pour cette version 3 729

Version publiée:

License:

BSD

Version de Ruby requise: None

Liens: