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|
def f1
puts 'foo-begin'
f2 { puts 'break'; break } # break jumps after this statement
puts 'foo-end'
end
def f2 &p
puts 'bar-begin'
f3 &p
puts 'bar-end'
end
def f3
puts 'baz-begin'
yield # unwinds to f1
puts 'baz-end'
end
f1
puts '------------'
# not all call-sites need to pass block thru
# proc.call also works, not only yield
def h1
puts 'foo-begin'
h2 { puts 'break'; break } # break jumps after this statement
puts 'foo-end'
end
def h2 &p
puts 'bar-begin'
$p = p
h3
puts 'bar-end'
end
def h3
puts 'baz-begin'
$p[] # unwinds to h1
puts 'baz-end'
end
h1
puts '------------'
# owner of proc != owner of block
#
def defp &p
$p = p
g2 &p # this is ok
end
def g1
puts 'foo-begin'
#$p = lambda do # the same error result if the following line is replaced by lambda call
defp do
begin
puts 'break' # break from proc-closure error
break
rescue LocalJumpError
puts 'ERROR 1'
end
end
puts 'foo-mid'
g2 &$p # this raises an error #3
puts 'foo-end'
rescue LocalJumpError
puts 'ERROR 4'
end
def g2 &p
puts 'bar-begin'
g3 &p
puts 'bar-end'
rescue LocalJumpError
puts 'ERROR 2'
end
def g3 &p
puts 'baz-begin'
1.times &p # break returns here, we need to decide now whether we can unwind or not
puts 'baz-end'
rescue LocalJumpError => e
puts 'ERROR 3' # rescued here
puts e
puts e.backtrace
end
g1
|
