Re^2: Overriding built-in function works only via import()?

Consequently it shouldn't work if the import() is called in the same package, right? (Untested)

Hence the perldocs should be clearer:

> perlsub#Overriding-Built-in-Functions Overriding may be done only by importing the name from a module at compile time--ordinary predeclaration isn't good enough.

A module is a .pm which supports importing with use It's normal practice to have its own package, but not necessarily so.

Cheers Rolf
_{(addicted to the Perl Programming Language and ☆☆☆☆ :)

Wikisyntax for the Monastery}

Comment on Re^2: Overriding built-in function works only via import()?

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Re^3: Overriding built-in function works only via import()? by haukex (Archbishop) on Feb 02, 2018 at 10:02 UTC
Consequently it shouldn't work if the import() is called in the same package, right? (Untested) Yep, looks like it: $ perl -wle '{ package Foo; sub import { {caller."::readpipe"} = sub {"Foo"} } } BEGIN { Foo->import() } print `xyz`' Foo $ perl -wle 'sub import { {caller."::readpipe"} = sub {"Foo"} } BEGIN { main->import() } print `xyz`' Can't exec "xyz": No such file or directory at -e line 2. [download]	[reply] [d/l]

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Re^3: Overriding built-in function works only via import()?
by haukex (Archbishop) on Feb 02, 2018 at 10:02 UTC

Consequently it shouldn't work if the import() is called in the same package, right? (Untested)

Yep, looks like it:

$ perl -wle '{ package Foo; sub import { *{caller."::readpipe"}
  = sub {"Foo"} } } BEGIN { Foo->import() } print `xyz`'
Foo

$ perl -wle 'sub import { *{caller."::readpipe"} = sub {"Foo"} }
  BEGIN { main->import() } print `xyz`'
Can't exec "xyz": No such file or directory at -e line 2.
[download]

[reply]
[d/l]