- string-tabulate proc lenprocedure
proc is a procedure that accepts an exact integer as its argument and returns a character. Constructs a string of size len by calling proc on each value from 0 (inclusive) to len (exclusive) to produce the corresponding element of the string. The order in which proc is called on those indexes is not specified.
Rationale: Although string-unfold is more general, string-tabulate is likely to run faster for the common special case it implements.