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Full Discussion: Can I use a variable with brace expansion?
Top Forums UNIX for Dummies Questions & Answers Can I use a variable with brace expansion? Post 302544041 by alister on Tuesday 2nd of August 2011 07:46:03 PM
Old 08-02-2011
Quote:
Originally Posted by bash man page
A sequence expression takes the form {x..y}, where x and y are either integers or single characters. When integers are supplied, the expression expands to each number between x and y, inclusive. When characters are supplied, the expression expands to each character lexicographically between x and y, inclusive. Note that both x and y must be of the same type.

Brace expansion is performed before any other expansions, and any characters special to other expansions are preserved in the result. It is strictly textual.
There is no 26 there when the brace expansion is attempted. The 1 and the literal string "$CAP" are an invalid sequence expression at that stage.

---------- Post updated at 07:20 PM ---------- Previous update was at 07:15 PM ----------

Brace expansion is an extension to the POSIX sh standard. Different posix-like shells perform it at different times. bash performs it before all other expansions while ksh leaves it for much later (after parameter expansion and command substitution and field splitting).

---------- Post updated at 07:46 PM ---------- Previous update was at 07:20 PM ----------

I forgot to mention, if you want to loop over the elements of an array, there's a much simpler way to do it:
Code:
for i in "${x[@]}"; do whatever; done

The * and @ subscripts are analogous to the $* and $@ special parameters used by the shell to handle script arguments.

Regards,
Alister
This User Gave Thanks to alister For This Post:
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LEARN ABOUT CENTOS

kpsewhich

KPSEWHICH(1)						      General Commands Manual						      KPSEWHICH(1)

NAME

       kpsewhich - standalone path lookup and and expansion for kpathsea

SYNOPSIS

       kpsewhich [options] [filenames]

DESCRIPTION

       This manual page is not meant to be exhaustive.	The complete documentation for this version of TeX can be found in the info file or manual
       Kpathsea: A library for path searching.

       kpsewhich is used as a standalone front-end of the kpathsea library that can be used to examine variables and find files.  When the -format
       option is not given, the search path used when looking for a file is inferred from the name given, by looking for a known extension.  If no
       known extension is found, the search path for TeX source files is used.

OPTIONS

       kpsewhich accepts the following options:

       -debug num
	      Set debugging flags.

       -D num Use a base resolution of num; the default, set by the installer, is typically 600.

       -dpi num
	      As -D.

       -engine string
	      Set $engine in the environment, which is used in some search paths.

       -expand-braces string
	      Print variable and brace expansion of string.

       -expand-path string
	      Print complete path expansion of string.

       -expand-var string
	      Print variable expansion of string.

       -format name
	      Use file type name.  See the info manual for a list of valid names, or use the -help option to print the list.

       -help  Print help message and exit.

       -interactive
	      Ask for additional filenames to look up.

       -mktex fmt
	      enable mktexfmt generation.  (fmt=pk/mf/tex/tfm)

       -mode string
	      Set device name for $MAKETEX_MODE to string; no default.

       -must-exist
	      Search the disk as well as ls-R if necessary.

       -no-mktex fmt
	      disable mktexfmt generation.  (fmt=pk/mf/tex/tfm)

       -path string
	      Search in the path string.

       -progname string
	      Set program name to string.

       -show-path name
	      Output search path for file type name.  See the info manual for a list of valid names, or use the -help option to print the list.

       -var-value variable
	      Print the expansion of variable.

       -version
	      Print version information and exit.

SEE ALSO

       mktexlsr(1), mktexmf(1), mktexpk(1), mktextfm(1).

Kpathsea 6.1.0							   1 March 2011 						      KPSEWHICH(1)
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