chickadee » srfi-14 » char-set<=

Returns true if every character set CS_I is a subset of character set CS_I+1.

Boundary cases:

 (char-set<=) => TRUE
 (char-set<= cs) => TRUE

Rationale: See char-set= for discussion of zero- and one-argument applications. Consider testing a list of char-sets for monotonicity with

(apply char-set<= cset-list)