Data commit

Task/String-case/Pascal/string-case.pas

@@ -0,0 +1,65 @@
+// Uppercase and Lowercase functions for a minimal standard Pascal
+// where no library routines for these operations exist
+PROGRAM upperlower;
+
+// convert a character to uppercase
+FUNCTION uch(ch: CHAR): CHAR;
+	BEGIN
+		uch := ch;
+		IF ch IN ['a'..'z'] THEN
+			uch := chr(ord(ch) AND $5F);
+	END;
+	
+// convert a character to lowercase
+FUNCTION lch(ch: CHAR): CHAR;
+	BEGIN
+		lch := ch;
+		IF ch IN ['A'..'Z'] THEN
+			lch := chr(ord(ch) OR $20);
+	END;
+	
+// toggle uper/lower case character
+FUNCTION ulch(ch: CHAR): CHAR;
+	BEGIN
+		ulch := ch;
+		IF ch IN ['a'..'z'] THEN ulch := uch(ch);
+		IF ch IN ['A'..'Z'] THEN ulch := lch(ch);
+	END;
+	
+// convert a string to uppercase
+FUNCTION ucase(str: STRING): STRING;
+	var i: Integer;
+	BEGIN
+		ucase := '';
+		FOR i := 1 TO Length(str) DO
+			ucase := ucase + uch(str[i]);
+	END;
+	
+// convert a string to lowercase
+FUNCTION lcase(str: STRING): STRING;
+	var i: Integer;
+	BEGIN
+		lcase := '';
+		FOR i := 1 TO Length(str) DO
+			lcase := lcase + lch(str[i]);
+	END;
+
+// reverse cases in a given string
+FUNCTION ulcase(str: STRING): STRING;
+	var i: Integer;
+	BEGIN
+		ulcase := '';
+		FOR i := 1 TO Length(str) DO
+			ulcase := ulcase + ulch(str[i]);
+	END;
+
+VAR
+	ab : STRING = 'alphaBETA';
+	
+BEGIN
+	// demonstration
+	Writeln('Original string : ',ab);
+	Writeln('Reversed case   : ',ulcase(ab));
+	Writeln('Upper case      : ',ucase(ab));
+	Writeln('Lower case      : ',lcase(ab));
+END.