subst(n)              Tcl Built-In Commands              subst(n)



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NAME
     subst - Perform backslash, command, and  variable  substitu-
     tions

SYNOPSIS
     subst ?-nobackslashes? ?-nocommands? ?-novariables? _s_t_r_i_n_g
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DESCRIPTION
     This command performs variable substitutions,  command  sub-
     stitutions,  and backslash substitutions on its _s_t_r_i_n_g argu-
     ment and returns the fully-substituted result.  The  substi-
     tutions  are  performed  in  exactly the same way as for Tcl
     commands.  As a result, the _s_t_r_i_n_g argument is actually sub-
     stituted  twice, once by the Tcl parser in the usual fashion
     for Tcl commands, and again by the _s_u_b_s_t command.

     If any of the -nobackslashes, -nocommands, or  - novariables
     are  specified, then the corresponding substitutions are not
     performed.  For example, if - nocommands  is  specified,  no
     command  substitution is performed:  open and close brackets
     are treated as ordinary characters with no special interpre-
     tation.

     Note: when it performs its  substitutions,  _s_u_b_s_t  does  not
     give any special treatment to double quotes or curly braces.
     For example, the script
          set a 44
          subst {xyz {$a}}
     returns ``xyz {44}'', not ``xyz {$a}''.


KEYWORDS
     backslash substitution, command substitution, variable  sub-
     stitution

















Tcl                     Last change: 7.4                        1