Difference between revisions of "Perl"
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:Concatenate $string and $addstring | :Concatenate $string and $addstring | ||
− | ;$string = s/<regexp>/<newvalue>/[g] | + | ;$string =~ s/<regexp>/<newvalue>/[g] |
:Substitute <regexp> with <newvalue> in $string. The g modifier makes the all occurrences of <regexp> are substituted. | :Substitute <regexp> with <newvalue> in $string. The g modifier makes the all occurrences of <regexp> are substituted. | ||
Revision as of 12:02, 11 March 2018
I'm leaving Perl, traded it for Python. Some shortcuts I'd like to remember
WARNING
Checking existence of a hash element creates the parent keys (autovivification). Always check top-down.
Things that do work
Print out the contents of $variable in a structured format.
use Data::Dumper;
print Dumper($variable);
- $var += <value>
- Add <value> to $var (works for -, *, / too)
- $string .= $addstring
- Concatenate $string and $addstring
- $string =~ s/<regexp>/<newvalue>/[g]
- Substitute <regexp> with <newvalue> in $string. The g modifier makes the all occurrences of <regexp> are substituted.
- $newstring = substr($string,start,length)
- Return substring of $string
- sprintf(format,$string)
- Return formatted string. format is e.g. "%.3f". Check Python:Strings#Advanced for all formats.