1less(3pm) Perl Programmers Reference Guide less(3pm)
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6 less - perl pragma to request less of something
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9 use less 'CPU';
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12 This is a user-pragma. If you're very lucky some code you're using will
13 know that you asked for less CPU usage or ram or fat or... we just
14 can't know. Consult your documentation on everything you're currently
15 using.
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17 For general suggestions, try requesting "CPU" or "memory".
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19 use less 'memory';
20 use less 'CPU';
21 use less 'fat';
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23 If you ask for nothing in particular, you'll be asking for "less
24 'please'".
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26 use less 'please';
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29 less has been in the core as a "joke" module for ages now and it hasn't
30 had any real way to communicating any information to anything. Thanks
31 to Nicholas Clark we have user pragmas (see perlpragma) and now "less"
32 can do something.
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34 You can probably expect your users to be able to guess that they can
35 request less CPU or memory or just "less" overall.
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37 If the user didn't specify anything, it's interpreted as having used
38 the "please" tag. It's up to you to make this useful.
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40 # equivalent
41 use less;
42 use less 'please';
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44 "BOOLEAN = less->of( FEATURE )"
45 The class method "less->of( NAME )" returns a boolean to tell you
46 whether your user requested less of something.
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48 if ( less->of( 'CPU' ) ) {
49 ...
50 }
51 elsif ( less->of( 'memory' ) ) {
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53 }
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55 "FEATURES = less->of()"
56 If you don't ask for any feature, you get the list of features that the
57 user requested you to be nice to. This has the nice side effect that if
58 you don't respect anything in particular then you can just ask for it
59 and use it like a boolean.
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61 if ( less->of ) {
62 ...
63 }
64 else {
65 ...
66 }
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69 This probably does nothing.
70 This works only on 5.10+
71 At least it's backwards compatible in not doing much.
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75perl v5.16.3 2013-02-26 less(3pm)