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Full Discussion: please explain this
Top Forums Shell Programming and Scripting please explain this Post 302140536 by radoulov on Saturday 13th of October 2007 06:58:35 PM
Old 10-13-2007
Quote:
Originally Posted by dummy_needhelp
[...]
But , can anybody can explain me in detail about this line

zsh 4.3.4% <file1 while read;do printf "%s=%d\n" "$REPLY" "${#$(<file)//[^$REPLY]}";[...]
I suppose you mean this: "${#$(<file)//[^$REPLY]}" (the rest is quite trivial).

This is nested expansion that goes like this:

1. $(<file) is equivalent to $(cat file) but a bit faster.
2. ${$(<file)//[^$REPLY]} means: remove(substitute with null) any character different than the content of the variable REPLY.
3. ${#$(<file)//[^$REPLY]} (the # sign) means: give me the number of characters in the variable ${$(<file)//[^$REPLY]}.

HTH
 

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LEARN ABOUT PHP

set_color

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,
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       o -b, --background Set the background color

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       Calling set_color normal will set the terminal color to whatever is the default color of the terminal.

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Version 1.23.1							  Sun Jan 8 2012						      set_color(1)
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