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Pascal


Pascal:: n. An Algol-descended language designed by Niklaus Wirth
   on the CDC 6600 around 1967--68 as an instructional tool for
   elementary programming.  This language, designed primarily to keep
   students from shooting themselves in the foot and thus extremely
   restrictive from a general-purpose-programming point of view, was
   later promoted as a general-purpose tool and, in fact, became the
   ancestor of a large family of languages including Modula-2 and
   Ada (see also bondage-and-discipline language).  The
   hackish point of view on Pascal was probably best summed up by a
   devastating (and, in its deadpan way, screamingly funny) 1981 paper
   by Brian Kernighan (of K&R fame) entitled "Why Pascal is
   Not My Favorite Programming Language", which was turned down by the
   technical journals but circulated widely via photocopies.  It was
   eventually published in "Comparing and Assessing Programming
   Languages", edited by Alan Feuer and Narain Gehani (Prentice-Hall,
   1984).  Part of his discussion is worth repeating here, because its
   criticisms are still apposite to Pascal itself after ten years of
   improvement and could also stand as an indictment of many other
   bondage-and-discipline languages.  At the end of a summary of the
   case against Pascal, Kernighan wrote:

9. There is no escape

This last point is perhaps the most important. The language is inadequate but circumscribed, because there is no way to escape its limitations. There are no casts to disable the type-checking when necessary. There is no way to replace the defective run-time environment with a sensible one, unless one controls the compiler that defines the "standard procedures". The language is closed.

People who use Pascal for serious programming fall into a fatal trap. Because the language is impotent, it must be extended. But each group extends Pascal in its own direction, to make it look like whatever language they really want. Extensions for separate compilation, FORTRAN-like COMMON, string data types, internal static variables, initialization, octal numbers, bit operators, etc., all add to the utility of the language for one group but destroy its portability to others.

I feel that it is a mistake to use Pascal for anything much beyond its original target. In its pure form, Pascal is a toy language, suitable for teaching but not for real programming.

Pascal has since been almost entirely displaced (by C) from the niches it had acquired in serious applications and systems programming, but retains some popularity as a hobbyist language in the MS-DOS and Macintosh worlds.