From f39bd08ad223ae831312c9896e18f2f05ca5cbd0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Ludovic=20Court=C3=A8s?= Date: Sat, 1 Sep 2012 19:21:06 +0200 Subject: [PATCH] Optimize `store-path?'. * guix/store.scm (store-path?): Check with `string-prefix?' instead of a regexp. --- guix/store.scm | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/guix/store.scm b/guix/store.scm index 1e6119ed18..3eedcbed57 100644 --- a/guix/store.scm +++ b/guix/store.scm @@ -414,13 +414,12 @@ Return #t on success." ;; Absolute path to the Nix store. (make-parameter "/nix/store")) -(define store-path? - (let ((store-path-rx - (delay (make-regexp - (string-append "^.*" (%store-prefix) "/[^-]{32}-(.+)$"))))) - (lambda (path) - "Return #t if PATH is a store path." - (not (not (regexp-exec (force store-path-rx) path)))))) +(define (store-path? path) + "Return #t if PATH is a store path." + ;; This is a lightweight check, compared to using a regexp, but this has to + ;; be fast as it's called often in `derivation', for instance. + ;; `isStorePath' in Nix does something similar. + (string-prefix? (%store-prefix) path)) (define (derivation-path? path) "Return #t if PATH is a derivation path."