jyapayne/Nim
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

fix #14404 foldr had the classic multiple evaluation bug (#14413)

Browse source
This commit is contained in:
Timothee Cour 2020-05-21 02:01:43 -07:00 • committed by GitHub
commit 5caaa4bf6f
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
1 changed files with 7 additions and 7 deletions
Download patch file Download diff file Expand all files Collapse all files

14
lib/pure/collections/sequtils.nim
View file

@ -843,8 +843,7 @@ template foldl*(sequence, operation, first): untyped =
digits = foldl(numbers, a & (chr(b + ord('0'))), "") digits = foldl(numbers, a & (chr(b + ord('0'))), "")
assert digits == "0815" assert digits == "0815"
var result: typeof(first) var result: typeof(first) = first
result = first
for x in items(sequence): for x in items(sequence):
let let
a {.inject.} = result a {.inject.} = result
@ -883,11 +882,11 @@ template foldr*(sequence, operation: untyped): untyped =
assert multiplication == 495, "Multiplication is (5*(9*(11)))" assert multiplication == 495, "Multiplication is (5*(9*(11)))"
assert concatenation == "nimiscool" assert concatenation == "nimiscool"
let s = sequence let s = sequence # xxx inefficient, use {.evalonce.} pending #13750
assert s.len > 0, "Can't fold empty sequences" let n = s.len
var result: typeof(s[0]) assert n > 0, "Can't fold empty sequences"
result = sequence[s.len - 1] var result = s[n - 1]
for i in countdown(s.len - 2, 0): for i in countdown(n - 2, 0):
let let
a {.inject.} = s[i] a {.inject.} = s[i]
b {.inject.} = result b {.inject.} = result
@ -1436,6 +1435,7 @@ when isMainModule:
assert subtraction == 7, "Subtraction is (5-(9-(11)))" assert subtraction == 7, "Subtraction is (5-(9-(11)))"
assert multiplication == 495, "Multiplication is (5*(9*(11)))" assert multiplication == 495, "Multiplication is (5*(9*(11)))"
assert concatenation == "nimiscool" assert concatenation == "nimiscool"
doAssert toSeq(1..3).foldr(a + b) == 6 # issue #14404
block: # mapIt + applyIt test block: # mapIt + applyIt test
counter = 0 counter = 0