concat(n) | Tcl Built-In Commands | concat(n) |
concat - Join lists together
concat ?arg arg ...?
This command joins each of its arguments together with spaces after trimming leading and trailing white-space from each of them. If all the arguments are lists, this has the same effect as concatenating them into a single list. It permits any number of arguments; if no args are supplied, the result is an empty string.
Although concat will concatenate lists, flattening them in the process (so giving the following interactive session):
% concat a b {c d e} {f {g h}} a b c d e f {g h}
it will also concatenate things that are not lists, as can be seen from this session:
% concat " a b {c " d " e} f" a b {c d e} f
Note also that the concatenation does not remove spaces from the middle of values, as can be seen here:
% concat "a b c" { d e f } a b c d e f
(i.e., there are three spaces between each of the a, the b and the c).
append(n), eval(n), join(n)
concatenate, join, lists
8.3 | Tcl |