When would `local $_' in a function ruin your day?

.NET C C++ CSS DBA General HTML Java JavaScript JSP JUnit MySQL Networking Oracle Perl Perl PHP PL/SQL RSS Software QA SQL Server Struts Unix Windows XHTML XML

Home Hot About Collections Index RSS Atom Ask

Tester Developer DBA Windows JAR DLL Files Certificates RegEx Links Q&A Biotech Phones Travel FAQ Forum

Home > Perl

✍: Guest

When your caller was in the middle for a while(m//g) loop
The /g state on a global variable is not protected by running local on it. That'll teach you to stop using locals. Too bad $_ can't be the target of a my() -- yet.

2013-09-20, 2583👍, 0💬

How do I replace every <TAB> character in a file with a comma?
How do I replace every <TAB> character in a file with a comma? perl -pi.bak -e 's/\t/,/g' myfile.txt 2013-09-18, 3386👍, 0💬

How do I print the entire contents of an array with Perl?
How do I print the entire contents of an array with Perl? To answer this question, we first need a sample array. Let's assume that you have an array that contains the name of baseball teams, like this: @teams = ('cubs', 'reds', 'yankees', 'dodgers'); If you just want to print the array with the arra... 2013-09-24, 2744👍, 0💬

How to concatenate strings with Perl?
How to concatenate strings with Perl? Method #1 - using Perl's dot operator: $name = 'checkbook'; $filename = "/tmp/" . $name . ".tmp"; Method #2 - using Perl's join function $name = "checkbook"; $filename = join "", "/tmp/", $name, ".tmp"; Method #3 - usual way of concatenating strings $filename = ... 2013-09-19, 2736👍, 0💬

How do I read command-line arguments with Perl?
How do I read command-line arguments with Perl? With Perl, command-line arguments are stored in the array named @ARGV. $ARGV[0] contains the first argument, $ARGV[1] contains the second argument, etc. $#ARGV is the subscript of the last element of the @ARGV array, so the number of arguments on the c... 2013-09-19, 2690👍, 0💬

How do I do < fill-in-the-blank > for each element in an array?
How do I do < fill-in-the-blank > for each element in an array? #!/usr/bin/perl -w @homeRunHitters = ('McGwire', 'Sosa', 'Maris', 'Ruth'); foreach (@homeRunHitters) { print "$_ hit a lot of home runs in one year\n"; } 2013-09-16, 2673👍, 0💬

What happens to objects lost in "unreachable" memory..... ?
What happens to objects lost in "unreachable" memory..... ? What happens to objects lost in "unreachable" memory, such as the object returned by Ob->new() in `{ my $ap; $ap = [ Ob->new(), \$ap ]; }' ? Their destructors are called when that interpreter thread shuts down. When the interp... 2013-09-20, 2656👍, 0💬

Assume that $ref refers to a scalar, an array, a hash or to some nested data structure. Explain the following statements:
Assume that $ref refers to a scalar, an array, a hash or to some nested data structure. Explain the following statements: $$ref; # returns a scalar $$ref[0]; # returns the first element of that array $ref- > [0]; # returns the first element of that array @$ref; # returns the contents of that ... 2013-09-23, 2643👍, 0💬

How do you match one letter in the current locale?
How do you match one letter in the current locale? /[^\W_\d]/ We don't have full POSIX regexps, so you can't get at the isalpha() <ctype.h> macro save indirectly. You ask for one byte which is neither a non-alphanumunder, nor an under, nor a numeric. That leaves just the alphas, which ... 2013-09-23, 2638👍, 0💬

When would `local $_' in a function ruin your day?
When would `local $_' in a function ruin your day? When your caller was in the middle for a while(m//g) loop The /g state on a global variable is not protected by running local on it. That'll teach you to stop using locals. Too bad $_ can't be the target of a my() -- yet. 2013-09-20, 2584👍, 0💬

.NET C C++ CSS DBA General HTML Java JavaScript JSP JUnit MySQL Networking Oracle Perl Perl PHP PL/SQL RSS Software QA SQL Server Struts Unix Windows XHTML XML

Home Hot About Collections Index RSS Atom Ask

Tester Developer DBA Windows JAR DLL Files Certificates RegEx Links Q&A Biotech Phones Travel FAQ Forum

All rights in the contents of this web site are reserved by the individual author. fyicenter.com does not guarantee the truthfulness, accuracy, or reliability of any contents.