Error: use curly braces to avoid double substitution

Hi Arie,

I just gave it a try on v11.6.0HF3:

when HTTP_REQUEST {
    log local0. "path: [HTTP::path]; extracted <[string range [HTTP::path] [expr {[string length "/contact"] + 1}] end]>"
    HTTP::path "/[string range [HTTP::path] [expr {[string length "/contact"] + 1}] end]"
    log local0. "new path: [HTTP::path]"
}

Log output as expected:

 tail -n 0 -f /var/log/ltm | grep -oE 'Rule .*$'
Rule /Common/rule_string : path: /contact/stephan; extracted 
Rule /Common/rule_string : new path: /stephan

Verification fine as well:

 tmsh list ltm rule rule_string > /shared/rule_verify
 tmsh load sys config merge verify file /shared/rule_verify
Validating configuration...
  /shared/rule_verify

Thanks, Stephan