NAME
       subst   -   Perform   backslash,   command,  and  variable
       substitutions

SYNOPSIS
       subst ?-nobackslashes? ?-nocommands? ?-novariables? string


DESCRIPTION
       This  command  performs  variable  substitutions,  command
       substitutions, and backslash substitutions on  its  string
       argument  and  returns  the fully-substituted result.  The
       substitutions are performed in exactly the same way as for
       Tcl  commands.   As  a  result,  the  string  argument  is
       actually substituted twice, once by the Tcl parser in  the
       usual  fashion  for  Tcl  commands, and again by the subst
       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 interpretation.

       Note:  when  it performs its substitutions, subst 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
