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BaltoStar_12467's avatar
BaltoStar_12467
Oct 02, 2015

BIG-IP : tcl boolean logic for string comparisons

F5 BIG-IP Virtual Edition v11.4.1 (Build 635.0) LTM on ESXi

What is correct syntax for boolean operations around string comparisons ?

set a "a"
set b "b"
set result 0
if { { $a eq "a" } && { $b eq "b" } } {
  set result 1
}

This compiles but throws a runtime exception :

expected boolean value but got " $a eq "a" " while executing "if { { $a eq "a" } && { $b eq "b" } ...

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  • Hannes_Rapp's avatar
    Hannes_Rapp
    Icon for Nimbostratus rankNimbostratus
    Oct 02, 2015

    Hello,

    Your logic is correct, however, the use of double curly brackets does not seem right.

    Try the following as your conditional statement: 

    if { ( $a eq "a" ) && ( $b eq "b" ) } {