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Top Forums Shell Programming and Scripting Problem on understanding the regexp command Post 302745027 by Yoda on Sunday 16th of December 2012 10:41:22 AM
Old 12-16-2012
I ran this regex in PERL to show you what exactly is happening:-
Code:
#!/usr/bin/perl

my $str = 'abc/def/gh';
my @r_1 = $str =~ /(\S+)\//;
my @r_2 = $str =~ /\/(\S+)/;
print "String: ", $str, "\nRegex 1: ", @r_1, "\nRegex 2: ", @r_2, "\n";

Code:
./regex.pl
String: abc/def/gh
Regex 1: abc/def
Regex 2: def/gh

In 1st regex, the string is getting split considering last / sign.
In 2nd regex, the string is getting split considering first / sign.
So basically whatever is there before the first & last / is getting omitted. I hope you understood.
This User Gave Thanks to Yoda For This Post:
 

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set_color(1)							       fish							      set_color(1)

NAME
set_color - set_color - set the terminal color set_color - set the terminal color Synopsis set_color [-v --version] [-h --help] [-b --background COLOR] [COLOR] Description Change the foreground and/or background color of the terminal. COLOR is one of black, red, green, brown, yellow, blue, magenta, purple, cyan, white and normal. o -b, --background Set the background color o -c, --print-colors Prints a list of all valid color names o -h, --help Display help message and exit o -o, --bold Set bold or extra bright mode o -u, --underline Set underlined mode o -v, --version Display version and exit Calling set_color normal will set the terminal color to whatever is the default color of the terminal. Some terminals use the --bold escape sequence to switch to a brighter color set. On such terminals, set_color white will result in a grey font color, while set_color --bold white will result in a white font color. Not all terminal emulators support all these features. This is not a bug in set_color but a missing feature in the terminal emulator. set_color uses the terminfo database to look up how to change terminal colors on whatever terminal is in use. Some systems have old and incomplete terminfo databases, and may lack color information for terminals that support it. Download and install the latest version of ncurses and recompile fish against it in order to fix this issue. Version 1.23.1 Sun Jan 8 2012 set_color(1)
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