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discard """
output: '''tada
1
2
3
ta da1 1
1 2
1 3
2 1
2 2
2 3
3 1
3 2
3 3
0
1
2
a1: A
a2: A
a1: B
a2: B
a1: C
a2: C
a1: D'''
"""
# Test first class iterator:
import strutils
iterator tokenize2(s: string, seps: set[char] = Whitespace): tuple[
token: string, isSep: bool] {.closure.} =
var i = 0
while i < s.len:
var j = i
if s[j] in seps:
while j < s.len and s[j] in seps: inc(j)
if j > i:
yield (substr(s, i, j-1), true)
else:
while j < s.len and s[j] notin seps: inc(j)
if j > i:
yield (substr(s, i, j-1), false)
i = j
iterator count3(): int {.closure.} =
yield 1
yield 2
yield 3
for word, isSep in tokenize2("ta da", WhiteSpace):
if not isSep:
stdout.write(word)
echo ""
proc inProc() =
for c in count3():
echo c
for word, isSep in tokenize2("ta da", WhiteSpace):
stdout.write(word)
for c in count3():
for d in count3():
echo c, " ", d
inProc()
iterator count0(): int {.closure.} =
# note: doesn't require anything in its closure (except 'state')
yield 0
iterator count2(): int {.closure.} =
# note: requires 'x' in its closure
var x = 1
yield x
inc x
yield x
# a first class iterator has the type 'proc {.closure.}', but maybe
# it shouldn't:
proc invoke(iter: iterator(): int {.closure.}) =
for x in iter(): echo x
invoke(count0)
invoke(count2)
# simple tasking:
type
TTask = iterator (ticker: int)
iterator a1(ticker: int) {.closure.} =
echo "a1: A"
yield
echo "a1: B"
yield
echo "a1: C"
yield
echo "a1: D"
iterator a2(ticker: int) {.closure.} =
echo "a2: A"
yield
echo "a2: B"
yield
echo "a2: C"
proc runTasks(t: varargs[TTask]) =
var ticker = 0
while true:
let x = t[ticker mod t.len]
if finished(x): break
x(ticker)
inc ticker
runTasks(a1, a2)
|
