INTERCAL is purposely different from all other computer languages in all ways but one; it is purely a written language, being totally unspeakable. An excerpt from the INTERCAL Reference Manual will make the style of the language clear:

It is a well-known and oft-demonstrated fact that a person whose work is incomprehensible is held in high esteem. For example, if one were to state that the simplest way to store a value of 65536 in a 32-bit INTERCAL variable is:

DO :1 <- #0$#256

any sensible programmer would say that that was absurd. Since this is indeed the simplest method, the programmer would be made to look foolish in front of his boss, who would of course have happened to turn up, as bosses are wont to do. The effect would be no less devastating for the programmer having been correct.

Caution! Under no circumstances confuse the mesh with the interleave operator, except under confusing circumstances!

The Woods-Lyons implementation was actually used by many (well, at least several) people at Princeton. The language has been recently reimplemented as C-INTERCAL and is consequently enjoying an unprecedented level of unpopularity; there is even an alt.lang.intercal newsgroup devoted to the study and ... appreciation of the language on Usenet.

The traditional "Hello, world!" program, written in C as

       #include 
       int main(void) { 
         printf("Hello, world!\\n"); 
         return 0; 
       }

appears as

       DO ,1 <- #13
       PLEASE DO ,1SUB#1 <- #234
       DO ,1SUB#2 <- #112
       DO ,1SUB#3 <- #112
       DO ,1SUB#4 <- #0
       DO ,1SUB#5 <- #64
       DO ,1SUB#6 <- #194
       DO ,1SUB#7 <- #48
       PLEASE DO ,1SUB#8 <- #22
       DO ,1SUB#9 <- #248
       DO ,1SUB#10 <- #168
       DO ,1SUB#11 <- #24
       DO ,1SUB#12 <- #16
       DO ,1SUB#13 <- #214
       PLEASE READ OUT ,1
       PLEASE GIVE UP

in INTERCAL.

Perhaps the weirdest thing about INTERCAL is that it is Turing-complete; that is, it can perform all of the calculations that a sane programming language can.

See also: Esoteric programming languages, Befunge.

External links

• INTERCAL home page on the Web.

• INTERCAL Resources on the Web, including several implementations