'\" '\" Copyright (c) 1993 The Regents of the University of California. '\" Copyright (c) 1994-1996 Sun Microsystems, Inc. '\" '\" See the file "license.terms" for information on usage and redistribution '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. '\" '\" RCS: @(#) $Id: eval.n,v 1.1.1.1 2007/07/10 15:04:23 duncan Exp $ '\" .so man.macros .TH eval n "" Tcl "Tcl Built-In Commands" .BS '\" Note: do not modify the .SH NAME line immediately below! .SH NAME eval \- Evaluate a Tcl script .SH SYNOPSIS \fBeval \fIarg \fR?\fIarg ...\fR? .BE .SH DESCRIPTION .PP \fBEval\fR takes one or more arguments, which together comprise a Tcl script containing one or more commands. \fBEval\fR concatenates all its arguments in the same fashion as the \fBconcat\fR command, passes the concatenated string to the Tcl interpreter recursively, and returns the result of that evaluation (or any error generated by it). Note that the \fBlist\fR command quotes sequences of words in such a way that they are not further expanded by the \fBeval\fR command. .SH EXAMPLE This procedure acts in a way that is analogous to the \fBlappend\fR command, except it inserts the argument values at the start of the list in the variable: .CS proc lprepend {varName args} { upvar 1 $varName var # Ensure that the variable exists and contains a list lappend var # Now we insert all the arguments in one go set var [\fBeval\fR [list linsert $var 0] $args] } .CE .SH KEYWORDS concatenate, evaluate, script .SH "SEE ALSO" catch(n), concat(n), error(n), list(n), subst(n), tclvars(n)