mirrors/janet
1
0
Fork 0
mirror of https://github.com/janet-lang/janet synced 2025-11-06 18:43:04 +00:00
Code Issues 1 Releases Wiki Activity

do not expand false branch more than once

Browse Source 
Fixes #1191
This commit is contained in:
primo-ppcg
2023-06-11 19:15:48 +07:00
parent 32c5b816ae
commit 2a7ea27bb7
2 changed files with 13 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
src/boot/boot.janet
View File

@@ -668,18 +668,20 @@
(def len (length bindings))
(if (= 0 len) (error "expected at least 1 binding"))
(if (odd? len) (error "expected an even number of bindings"))
(def res (gensym))
(defn aux [i]
(if (>= i len)
tru
~(do (set ,res ,tru) true)
(do
(def bl (in bindings i))
(def br (in bindings (+ 1 i)))
(if (symbol? bl)
~(if (def ,bl ,br) ,(aux (+ 2 i)) ,fal)
~(if (def ,bl ,br) ,(aux (+ 2 i)))
~(if (def ,(def sym (gensym)) ,br)
(do (def ,bl ,sym) ,(aux (+ 2 i)))
,fal)))))
(aux 0))
(do (def ,bl ,sym) ,(aux (+ 2 i))))))))
~(do
(var ,res nil)
(if ,(aux 0) ,res ,fal)))
(defmacro when-let
"Same as `(if-let bindings (do ;body))`."