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comparetcleval

Use comparison operator in a variable in tcl if statement

I would like to use the comparison operator like == >= and so in in a variable as shown in the following example. I can not get it to work as intended a i bet I use the eval statement wrong here. Can anyone help me out?

set distance 4
set rule "=="
set tolerance 4

if { ![ eval [ $distance $rule $tolerance ] ] } { puts "distance is equal to tolerance" } else { puts "bailout" }
Solution

  • You may use "expr" instead of "eval":

    set distance 4
set rule "=="
set tolerance 4

if { ! [expr $distance $rule $tolerance] } {
    puts "distance is equal to tolerance"
} else {
    puts "bailout"
}