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|
=begin
The following gobals have local scope:
$1 .. $9 NTH_REF not-aliasable
$& BACK_REF
$+ BACK_REF
$` BACK_REF
$' BACK_REF
$~ GVAR
$_ GVAR
True globals:
$*
$?
$<
$>
$!
$@
$;
$=
$.
$/
$~
$+
$_
$"
$&
$.
$,
$\
$$
$'
$`
$$
$0
$/
=end
require 'English'
puts "CHILD_STATUS = '#{$CHILD_STATUS}'"
puts "DEFAULT_INPUT = '#{$DEFAULT_INPUT}'"
puts "-------------------------------"
def foo
"cat" =~ /(c)(a)(t)/
puts "foo:1"
puts global_variables.join(' ')
puts "$1 = #{$1}"
puts
bar()
puts "foo:2"
puts global_variables.join(' ')
puts "$1 = #{$1}"
puts
baz()
puts "foo:3"
puts global_variables.join(' ')
puts "$1 = #{$1}"
puts
end
def bar
"bo" =~ /(b)(o)/
puts "bar:1"
puts global_variables.join(' ')
puts "$1 = #{$1}"
puts
end
def baz
puts "baz:1"
puts global_variables.join(' ')
puts "$1 = #{$1}"
puts
end
foo
# $! variable is real global
def exc
$! = NameError.new "bogus"
begin
begin
$" = 'foo'
rescue NameError
puts "Message 1: #{$!}"
display_message
$! = 'bar'
end
rescue TypeError
puts "Message 3: #{$!}"
end
puts "Message 4: #{$!}"
end
def display_message
puts "Message 2: #{$!}"
end
exc
puts "Message 5: #{$!}"
# testing $_ - it's local scoped global yet can be aliased
# => RubyOps.GetGlobal needs to get the current environment
def test_gets
gets
puts "Gets returned 1: '#{$_}'"
puts "Gets returned 1: '#{$FOO}'"
dump_gets
end
def dump_gets
puts "Gets returned 2: '#{$_}'"
end
$X = 'X'
alias $_ $X # alias hides the real global
alias $FOO $_
alias $BAR $`
test_gets
|
