From: ts <decoux@...>
Date: 2003-05-31T00:20:41+09:00
Subject: Re: local variable and local variable in block behave differently

>>>>> "a" == ahoward  <ahoward@fsl.noaa.gov> writes:

 Well, it's more

a> my best guess is that:

a>   1.times do
a>     ####
a>     #### here we are in a block
a>     ####
a>     if false
a>       ####
a>       #### assignment is parsed but not executed, 'a' (block-local) is now nil
a>       ####
a>       a = ""

 at compile time, ruby see a block local variable 'a', this variable will
 be created (at runtime) at the first assignement

a>     else
a>       ####
a>       #### at this point, there is no 'a' in *scope*, only a block-local 'a'
a>       #### thus the following block creates a new block-local 'a'
a>       ####
a>       1.times { a = "a" }

 at runtime this is the first assignement, and the variable is created
 inside the second block

a>     end
a>     ####
a>     #### these statements operate on the only symbol known as 'a' at this
a>     #### point, which happen to be the *first* block-local a.  this is not the
a>     #### same thing as scope, since blocks do not introduce a new scope.
a>     ####
a>     puts defined? a # => local-variable(in-block)

 ruby say that it has seen a local variable at compile time

a>     puts a          # => nil

 and in this block, the local variable was not assigned


Guy Decoux