INTERCAL, short for Compiler Language With No Pronounceable Acronym, is a parody programming language created by Don Woods and James Lyon in 1972. Developed at Princeton University, INTERCAL was designed as a satire of the programming languages of the time, particularly FORTRAN, COBOL, and Assembly language, all of which were becoming more complex and laden with unintuitive syntax. The creation of INTERCAL was a humorous critique of the growing complexity and, at times, absurdity of these languages, mocking their conventions by making its own syntax intentionally difficult and nonsensical.
The core philosophy of INTERCAL is that it is deliberately designed to be as frustrating and obscure as possible. The language avoids any features that might make programming easy or logical, and instead introduces highly unconventional commands and structures. For instance, one of its most infamous commands is PLEASE. If a programmer does not use PLEASE often enough in their code, the program will refuse to compile, citing the programmer's lack of politeness. On the other hand, if the word "please" is overused, the compiler will reject the code for being too polite. This satirical twist is one of many bizarre quirks meant to frustrate anyone attempting to write a program in INTERCAL.
Here is an example of an INTERCAL program that prints "Hello, world!" — a standard exercise in most programming languages, but far from simple in INTERCAL:
DO ,1 <- #13
PLEASE DO ,1 SUB #1 <- #238
DO ,1 SUB #2 <- #108
DO ,1 SUB #3 <- #112
DO ,1 SUB #4 <- #0
DO ,1 SUB #5 <- #64
DO ,1 SUB #6 <- #194
DO ,1 SUB #7 <- #48
DO ,1 SUB #8 <- #22
DO ,1 SUB #9 <- #248
PLEASE WRITE OUT ,1
PLEASE GIVE UPEven a trivial task like printing a string requires an arcane series of commands, reflecting the language's goal of being purposefully convoluted.
INTERCAL features a number of unique elements designed to mock the programming constructs found in other languages. For example, the language includes the use of "come from" statements, a spoof of the "goto" statements found in many early programming languages. The "come from" construct in INTERCAL allows a program to specify where control can be taken from another part of the code, adding to the confusing and erratic flow control possibilities.
Though not widely used in any practical sense, INTERCAL has achieved a cult following due to its humorous take on programming. It serves as an inside joke among computer scientists and programmers, often cited in discussions of esoteric programming languages. The very act of attempting to write code in INTERCAL becomes a humorous challenge, a way for programmers to poke fun at their profession and the tools they use.
In addition to its academic roots, INTERCAL also embodies the early hacker culture that embraced both technical proficiency and humor. Despite its obscurity, the language still occasionally attracts programmers who are interested in exploring its satirical complexity as a way to test their patience and skills. There have been updates and implementations of INTERCAL over the years, including versions that run on modern systems, and even graphical versions like CLC-INTERCAL, which extend the parody to visual programming environments.
In conclusion, INTERCAL stands as a testament to the playful side of computer science, a deliberately perverse programming language created to lampoon the overly serious and often confusing languages that dominated the field in the early 1970s. While no one would use INTERCAL for a serious project, its existence has brought humor and levity to a field that can sometimes take itself too seriously. Through its quirks, such as the need for politeness, and its nonsensical structure, INTERCAL remains one of the most beloved examples of an esoteric language in programming history.