String operators ~ and x

Concatenate with ~, repeat with x — and why they aren't + and *.

Raku keeps string and numeric operations on separate symbols, so a value's type is never guessed from the operator. Strings concatenate with ~ and repeat with x.

Concatenation — ~ #

say "ab" ~ "cd";
say "foo" ~ 42;

abcd
foo42

The second operand is coerced to Str, so "foo" ~ 42 works and gives foo42.

Repetition — x #

x repeats a string a given number of times. (Its list cousin xx repeats a value into a list — a different operator.)

say "ab" x 3;
say "=" x 10;

ababab
==========

Why not + and * #

In Raku + and * are always numeric. "3" + "4" is 7 (the strings are coerced to numbers), never "34". Concatenation therefore needs its own operator, ~, and string repetition needs x.

say "3" + "4";
say "3" ~ "4";

7
34

Notes #

• The unary/prefix ~ coerces to Str: ~42 is "42". As an infix it concatenates.
• x requires a number on the right; "ab" x 2.9 truncates the count to 2.