Problem Statement

Idiomatically determine all the lowercase and uppercase letters   (of the Latin [English] alphabet)   being used currently by a computer programming language. The method should find the letters regardless of the hardware architecture that is being used (ASCII, EBCDIC, or other).

Display the set of all: that can be used (allowed) by the computer program, where   letter   is a member of the Latin (English) alphabet:     a ──► z     and     A ──► Z.

You may want to mention what hardware architecture is being used, and if applicable, the operating system.

Let's start with the solution:

func printChars(from,to,st){
	set arr=[];
	for(c=from;to;1){
		arr->push(string.byte(c));
	}
	log(st," ",arr);
	del arr;
}

printChars(0x61,0x7a,"lowercase");
printChars(0x41,0x5a,"UPPERCASE");