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Full Discussion: A $(( expression )) bug?
Top Forums UNIX for Advanced & Expert Users A $(( expression )) bug? Post 302982344 by Don Cragun on Wednesday 28th of September 2016 08:05:38 AM
Old 09-28-2016
In an arithmetic evaluation, the value of a variable can be specified by expanding the variable (i.e. $var or ${var}) or by just giving the variable name (i.e. var). But the expression that is the numeric evaluation of the length of the string that is the value of a variable must use the expansion of the variable that produces that number (i.e. ${#var}); you cannot skip the ${ and } when you are using shell variable expansion operators like ${#var} or ${var%%pattern} or ${var:offset:length}.
 

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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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