Perl operators and precedence
Questions tagged [perlop]
6 questions
6
votes
3 answers
Is there a name for the special variable %+?
I was wondering if there was an operator name for %+, so instead of code like:
/(?\w+)/;
...
my $whatever=$+{CaptureName};
I could use something more readable:
use English;
/(?\w+)/;
...
my $whatever=$?????{CaptureName};
Michael Goldshteyn
- 71,784
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4
votes
1 answer
Why using utf8 patterns within perl substitute(s) and match(m) operators within one-liners does not work?
I found this issue when using Perl's one-liners for substituting some utf8 text in files.
I am aware of hacks at How to handle utf8 on the command line (using Perl or Python)?. They don't work for this case. OS is linux, locate is set to utf8
# make…
okharch
- 387
- 2
- 10
2
votes
2 answers
Why "?:" operator cannot return list?
Why ?: operator can not return list?
my $hash = {
...
($row->active?checked=>1:()),
};
The DOC say nothing about scalar or list context
UPD
Another example:
@list = 2,3; # CORRECT
@list = 1? 2,3 : (); # Syntax error
Why first is…
Eugen Konkov
- 22,193
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1
vote
2 answers
What is precedence in this expression?
When I run this program:
print(rand*100)
I get values from [0,1) range.
But for this:
print(100*rand)
I get values from [0,100) range.
What is precedence here? and why first expression does not return values from [0,100) range?
Eugen Konkov
- 22,193
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1
vote
4 answers
How to check if a file name contains directory info?
I would like to check if a file name has any directory information within it, preferably without using a system dependent hack like index($file_name,'/')!=-1. I know of the File::Spec module, but can't seem to find a way to use that module to make…
Michael Goldshteyn
- 71,784
- 24
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-1
votes
4 answers
Perl dereferencing in non-strict mode
In Perl, if I have:
no strict;
@ARY = (58, 90);
To operate on an element of the array, say it, the 2nd one, I would write (possibly as part of a larger expression):
$ARY[1] # The most common way found in Perldoc's idioms.
Though, for some reason…
g.cze
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