Re: can this be turned into a compile-time error?

in reply to Re: Should chomping a constant always raise an error?
in thread Should chomping a constant always raise an error?

sub modify {
   chomp( $_[0] );
   # whatever else happens, you've just potentially modified $_[0]
}

modify('fred');
# What would you expect to happen to 'fred'?
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Great example. For those who did not try it out, it causes a runtime exception:

Modification of a read-only value attempted at /tmp/t.pl line 2.
[download]

Can modify somehow be declared to only take a modifiable parameter, so that we can have a compile-time error (as happens with the core chomp)?

Can't modify constant item in modify at -e line 1, at end of line
Execution of -e aborted due to compilation errors.
[download]

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Re^2: can this be turned into a compile-time error? by QM (Parson) on Mar 11, 2005 at 18:54 UTC
Can modify somehow be declared to only take a modifiable parameter, so that we can have a compile-time error (as happens with the core chomp)? Playing Devil's Advocate, will this work? `chomp(foo(",",@list))` [download] Don't know? How about this? `chomp(join(",",@list))` [download] It seems, off the top of my naive head, that the argument to `chomp` would have to be an l-value to be guaranteed to be modifiable. Is that what you want? -QM -- Quantum Mechanics: The dreams stuff is made of	[reply] [d/l] [select]

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Re^2: can this be turned into a compile-time error?
by QM (Parson) on Mar 11, 2005 at 18:54 UTC

Can modify somehow be declared to only take a modifiable parameter, so that we can have a compile-time error (as happens with the core chomp)?

chomp(foo(",",@list))
[download]

chomp(join(",",@list))
[download]

chomp

Is that what you want?

-QM
--
Quantum Mechanics: The dreams stuff is made of

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