TCL: tcl command execute by variable

Question

I am a beginner with tcl. I am trying to use primetime execute command, but it can't accept variable. For example:

set var "get_timing_paths -rise_from A -rise_to B"
set path0001 [$var]

But it doesn't work. The things I want to do is

set path0001 [get_timing_paths -rise_from A -rise_to B]

but I need to seperate it.

Thank you for your answer.

Sergei Golovan · Accepted Answer · 2017-08-09 10:40:33Z

5

If you're using Tcl/Tk 8.5 or newer, it'd be better to use the list expansion operator {*} instead of eval:

set var "get_timing_paths -rise_from A -rise_to B"
set path0001 [{*}$var]

It's a bit faster and safer.

answered Aug 9, 2017 at 10:40

Sergei Golovan

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2 Comments

It's quite a lot faster. Possibly hugely so if you build the command to run with list.

I was using exec. So, I used it like this: set TTY "| tee /dev/tty" if [catch {exec sh s.sh {*}$TTY} result] { puts "Caught"}

Dinesh · Accepted Answer · 2017-08-09 05:08:46Z

0

Just add eval while calling the command.

set path0001 [eval $var]

Reference : eval

answered Aug 9, 2017 at 5:08

Dinesh

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