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# Example program showing 'return-continuation-until-mark' return other values
# alongside continuations.
#
# Print out a given list of numbers.
#
# Expected output:
# 1
# 2
# 3
def main [
local-scope
l:&:list:num <- copy 0
l <- push 3, l
l <- push 2, l
l <- push 1, l
k:continuation, x:num, done?:bool <- call-with-continuation-mark create-yielder, l
{
break-if done?
$print x 10/newline
k, x:num, done?:bool <- call k
loop
}
]
def create-yielder l:&:list:num -> n:num, done?:bool [
local-scope
load-ingredients
{
done? <- equal l, 0
break-if done?
n <- first l
l <- rest l
return-continuation-until-mark n, done?
loop
}
# A function that returns continuations shouldn't get the opportunity to
# return. Calling functions should stop calling its continuation after this
# point.
return-continuation-until-mark -1, done?
assert 0/false, [called too many times, ran out of continuations to return]
]
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