On 4/30/24 04:14, Alan Wagner-Krankel wrote:
The results of these conditional expressions using recursive glob operators were unexpectedly different:[[ f0 = **/f? ]] && print true || print falsefalsesetopt extendedglob [[ f0 = (*/)#f? ]] && print true || print falsetrue
A couple things about [[: ``` Pattern metacharacters are active for the pattern arguments; the patterns are the same as those used for filename generation, see zshexpn(1), but there is no special behaviour of ‘/' nor initial dots, and no glob qualifiers are al‐ lowed. ``` That last bit about glob qualifiers is out of date since you can now use them to force filename generation on in [[. but the point is you aren't doing filename generation in [[ (by default), which is where **/ is shorthand for (*/)#. pattern matching/globbing is tightly coupled to filename generation in unix shells but there are difference. Even when you use a glob qualifier to force filename generation to happen, you still wasn't going to get the behavior you desired since the pattern would've underwent filename generation before the comparison that [['s =/== does. % (set -x; [[ f0 = **/f?(#qN) ]]; touch f2; [[ f0 = **/f?(#qN) ]]) +zsh:3> [[ f0 = ]] +zsh:3> touch f2 +zsh:3> [[ f0 = f2 ]]
Since **/ is a shorthand version of (*/)#, it seems like they both should have returned 'true'. The comparisons behave the same when there is at least one directory in the path:[[ d1/f1 = **/f? ]] && print true || print falsetruesetopt extendedglob [[ d1/f1 = (*/)#f? ]] && print true || print falsetrue I came across this because it affects the behavior of zmv, via a test that filters filenames (line 254 in zsh5.9). An example:mkdir d1 d1/d2 touch f0 d1/f1 d1/d2/f2 print -rl -- **/f?d1/d2/f2 d1/f1 f0autoload zmv zmv -n '**/f?' '$f.txt'mv -- d1/d2/f2 d1/d2/f2.txt mv -- d1/f1 d1/f1.txtzmv -n '(*/)#f?' '$f.txt'mv -- d1/d2/f2 d1/d2/f2.txt mv -- d1/f1 d1/f1.txt mv -- f0 f0.txt I think both zmv calls should have attempted to update the 'f0' file in the base directory. Am I missing something? Thanks, Awk
I'll leave zmv's implementation for someone else to answer but i suspect the reasoning is similar.