How to empty a list in Tcl?

Question

How do you empty a list in Tcl efficiently?

I have tried using lreplace to empty a list, for example:

set lst "a b c d e"  
lreplace $lst 0 [[llength $lst] - 1]  # replace all content in the list with "".

Answer 1

The empty string is an efficient value to use.

set lst {}

You can use [list] with no arguments instead of {}; that compiles to the same thing.

Answer 2

How about: set lst [list]

References: list