TCL string concat

What is the recommended way of concatenation of strings?

4 Answers

Tcl does concatenation of strings as a fundamental operation; there's not really even syntax for it because you just write the strings next to each other (or the variable substitutions that produce them).

set combined $a$b 

If you're doing concatenation of a variable's contents with a literal string, it can be helpful to put braces around the variable name or the whole thing in double quotes. Or both:

set combined "$a${b}c d" 

Finally, if you're adding a string onto the end of a variable, use the append command; it's faster because it uses an intelligent memory management pattern behind the scenes.

append combined $e $f $g # Which is the same as this: set combined "$combined$e$f$g" 

Use append.

set result "The result is " append result "Earth 2, Mars 0" 

If they are contained in variables, you can simply write "$a$b".

These days, you can concatenate two literal strings using the "string cat" command:

set newstring [string cat "string1" "string2"]