<HTML><HEAD><TITLE>Tcl Built-In Commands - subst manual page</TITLE></HEAD><BODY>
<H3><A NAME="M2">NAME</A></H3>
subst - Perform backslash, command, and variable substitutions
<H3><A NAME="M3">SYNOPSIS</A></H3>
<B>subst </B>?<B>-nobackslashes</B>? ?<B>-nocommands</B>? ?<B>-novariables</B>? <I>string</I><BR>
<H3><A NAME="M4">DESCRIPTION</A></H3>
This command performs variable substitutions, command substitutions,
and backslash substitutions on its <I>string</I> argument and
returns the fully-substituted result.
The substitutions are performed in exactly the same way as for
Tcl commands.
As a result, the <I>string</I> argument is actually substituted twice,
once by the Tcl parser in the usual fashion for Tcl commands, and
again by the <I>subst</I> command.
<P>
If any of the <B>-nobackslashes</B>, <B>-nocommands</B>, or
<B>-novariables</B> are specified, then the corresponding substitutions
are not performed.
For example, if <B>-nocommands</B> is specified, no command substitution
is performed: open and close brackets are treated as ordinary characters
with no special interpretation.
<P>
Note: when it performs its substitutions, <I>subst</I> does not
give any special treatment to double quotes or curly braces. For
example, the script
<PRE><B>set a 44
subst {xyz {$a}}</B></PRE>
returns ``<B>xyz {44}</B>'', not ``<B>xyz {$a}</B>''.
<H3><A NAME="M5">SEE ALSO</A></H3>
<B><A HREF="../TkCmd/eval.htm">eval</A></B>
<H3><A NAME="M6">KEYWORDS</A></H3>
<A href="../Keywords/B.htm#backslash substitution">backslash substitution</A>, <A href="../Keywords/C.htm#command substitution">command substitution</A>, <A href="../Keywords/V.htm#variable substitution">variable substitution</A>
<HR><PRE>
<A HREF="../copyright.htm">Copyright</A> © 1994 The Regents of the University of California.
<A HREF="../copyright.htm">Copyright</A> © 1994-1996 Sun Microsystems, Inc.
<A HREF="../copyright.htm">Copyright</A> © 1995-1997 Roger E. Critchlow Jr.</PRE>
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