Re^2: disable functions if module not installed

in reply to Re: disable functions if module not installed
in thread disable functions if module not installed

require returns true on success, and string-eval eats memory :)

BEGIN { $is_magick = eval {require Image::Magick;}; }


C:\>perl -e"print require CGI;"
1
C:\>perl -e"print require CGIshamalamadingdong;"
Can't locate CGIshamalamadingdong.pm in @INC
[download]

Comment on Re^2: disable functions if module not installed Download Code

Replies are listed 'Best First'.
Re^3: disable functions if module not installed by almut (Canon) on Nov 04, 2008 at 13:59 UTC
require returns true on success, yes, and false (`undef`) otherwise. That was the idea :) string-eval eats memory Why would that be (in this case, where the string is just a few bytes)? Any tests/data to prove the claim? `C:\>perl -e"print require CGI;" 1 C:\>perl -e"print require CGIshamalamadingdong;" Can't locate CGIshamalamadingdong.pm in @INC` [download] Not sure what this is meant to demonstrate — I thought we were talking about `eval "require ..."`: `$ perl -E '$ok = eval "require CGI" ? 1:0; say $ok' 1 $ perl -E '$ok = eval "require CGIshamalamadingdong" ? 1:0; say $ok' 0` [download] (note: swap single and double quotes if you're on Windows)	[reply] [d/l] [select]

Replies are listed 'Best First'.

Re^3: disable functions if module not installed
by almut (Canon) on Nov 04, 2008 at 13:59 UTC

require returns true on success,

yes, and false (undef) otherwise. That was the idea :)

string-eval eats memory

Why would that be (in this case, where the string is just a few bytes)? Any tests/data to prove the claim?

C:\>perl -e"print require CGI;" 1 C:\>perl -e"print require CGIshamalamadingdong;" Can't locate CGIshamalamadingdong.pm in @INC
[download]

Not sure what this is meant to demonstrate — I thought we were talking about eval "require ...":

$ perl -E '$ok = eval "require CGI" ? 1:0; say $ok'
1
$ perl -E '$ok = eval "require CGIshamalamadingdong" ? 1:0; say $ok'
0
[download]

(note: swap single and double quotes if you're on Windows)

[reply]
[d/l]
[select]

In Section Seekers of Perl Wisdom