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|
discard """
output: '''
x
e
done
'''
"""
#[
xxx move this to tests/stdlib/tasyncjs.nim
]#
import std/asyncjs
block:
# demonstrate forward definition for js
proc y(e: int): Future[string] {.async.}
proc e: int {.discardable.} =
echo "e"
return 2
proc x(e: int): Future[void] {.async.} =
var s = await y(e)
if e > 2:
return
echo s
e()
proc y(e: int): Future[string] {.async.} =
if e > 0:
return await y(0)
else:
return "x"
discard x(2)
import std/sugar
from std/strutils import contains
var witness: seq[string]
proc fn(n: int): Future[int] {.async.} =
if n >= 7:
raise newException(ValueError, "foobar: " & $n)
if n > 0:
var ret = 1 + await fn(n-1)
witness.add $(n, ret)
return ret
else:
return 10
proc main() {.async.} =
block: # then
let x = await fn(4)
.then((a: int) => a.float)
.then((a: float) => $a)
doAssert x == "14.0"
doAssert witness == @["(1, 11)", "(2, 12)", "(3, 13)", "(4, 14)"]
doAssert (await fn(2)) == 12
let x2 = await fn(4).then((a: int) => (discard)).then(() => 13)
doAssert x2 == 13
block: # catch
var reason: Error
await fn(6).then((a: int) => (witness.add $a)).catch((r: Error) => (reason = r))
doAssert reason == nil
await fn(7).then((a: int) => (discard)).catch((r: Error) => (reason = r))
doAssert reason != nil
doAssert reason.name == "Error"
doAssert "foobar: 7" in $reason.message
echo "done" # justified here to make sure we're running this, since it's inside `async`
discard main()
|