trusty (3) eval.3tcl.gz

NAME

       eval - Evaluate a Tcl script

SYNOPSIS

       eval arg ?arg ...?
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DESCRIPTION

       Eval  takes  one or more arguments, which together comprise a Tcl script containing one or more commands.
       Eval concatenates all its arguments in the same fashion as the concat 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 list command quotes sequences of words in such a way that they  are  not
       further expanded by the eval command.

EXAMPLE

       This  procedure  acts  in  a way that is analogous to the lappend command, except it inserts the argument
       values at the start of the list in the variable:
              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 [eval [list linsert $var 0] $args]
              }

KEYWORDS

       concatenate, evaluate, script

SEE ALSO

       catch(3tcl), concat(3tcl), error(3tcl), list(3tcl), subst(3tcl), tclvars(3tcl)