Tcl question: expansion of variable names
neumann at wu.ac.at
Tue Sep 4 19:45:50 UTC 2018
On 04.09.18 15:53, Ryan Schmidt wrote:
> I've never been quite clear on the benefits of using [list] vs just making a string, since a string is a list, and I seem to use them interchangeably.
in case the interpolated variables have values that have no Tcl meaning,
one can use
set a 10
set b 20
set l1 "$a $b"
set l2 [list $a $b]
and get the same result from double quotes and [list], when e.g. using
list operations like
puts [lindex $l1 1]
puts [lindex $l2 1]
however, when e.g. variable "a" has a value like "1 2" the output will
since l1 consists now of three blank separates values,
where l2 keeps the the value a regardless of its contents a properly braced
as first element of the list. Same happens, when "a" is e.g. empty, etc.
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