in reply to Windows Path

Welll (drawl) .. pretty nice, but .. how about a nice little DOSKEY macro assisted by Perl, to give you a nice UNI*-style path listing if you have HOMEDRIVE defined in your ENV, or DOS-style with proper right-leaning slashes if not? ($ENV{'HOMEDRIVE'} maps a drive to the UNI* root `/'; on my system that's `D:').

Could come in handy. 

 ms shell> DOSKEY RPATH=perl -e "@wp=split ';', $ENV{path};@wp=map {s#
+\\#/#g; $_;} @wp; @PP=($uROOT=$ENV{'HOMEDRIVE'})? map {s#\A$uROOT##i;
+ s#\A([^^$uROOT]) (?:\:\/)#'/'. lc ${1} .((${1} eq $uROOT)? '':'/')#x
+ei;$_;} @wp : @wp; @PP=map{s#\:##; $_;} @PP; print join qq'\n', @PP;"

[download]

This is equivalent to the one-liner below (DOSKEY macros cause us to generate rather obfuscated Perl, don't they :-)? 

perl -e "@wp=split ';', $ENV{path};@wp=map {s#\\#/#g; $_;} @wp; @PP=($
+uROOT=$ENV{'HOMEDRIVE'})? map {s#\A$uROOT##i; s#\A([^$uROOT]) (?:\:\/
+)#'/'. lc $1 .(($1 eq $uROOT)? '':'/')#xei;$_;} @wp : @wp; @PP=map{s#
+\:##; $_;} @PP; print join qq'\n', @PP;"

[download]

On my system, to illustrate what I mean, this is output:


/console
/usr/local/bin/java/bin
/MingW32/gcc-2.95.2/bin
/bin
/ActivePERL/bin
/usr/bin
/e/scr
/c/WINNT/system32
/c/WINNT
/c/stdJava/bin
/usr/tmake/bin

Soren Andersen

Edited 2003.07.27 just clean-up.

Update 2003.08.03 -- A little observation regarding this old posting.

The code above would never have worked in MS Win9x, which has a 127-char limit on length of command lines. I have created a revised version of it which does work on Win9x, at the cost of some additional support complexity...

Update 2003.08.18 -- Refactored again since some temporary brain misfire cleared and I recalled the availability of the \l | \L operators to do what I was trying to accomplish with an eval.
DOSKEY macro in the form it takes as a macro file .mac on disk
PUP=perl -MEnv"=PATH,D0" -le"print join qq/\n/,(grep{($$D0&&s#\A$$D0##
+i)or s#\A([A-Z]):#/\l$$1#i}map{s#\\#/#g;$$_}split(';',$$PATH))"

[download]
To support this, one needs to set a variable %D0% in the environment:
     SET D0=%HOMEDRIVE%

Obviously this is little more than a toy, there is very little utility to it. Still, I had some fun figuring out how to code it ;-).

The doubled-dollar signs ($$) in the code above are not dereferencing of anything in perl, they are there because as a macro on disk, the first $ will be eaten when the macro is read in by the Windows shell interpreter. They must be removed if the macro is input manually.

In Section Cool Uses for Perl