Editing Pascal (programming language) (section)

==Reception==
Pascal generated a wide variety of responses in the computing community, both critical and complimentary.

===Early criticism===
Wirth's initial definition of the language was widely criticized. In particular, [[Nico Habermann]] commented in his "Critical Comments on the Programming Language Pascal" (1973) that many of its constructs were poorly defined, in particular for [[Data type|data types]], [[Range (computer programming)|ranges]], [[Record (computer science)|structures]], and [[goto]].<ref>{{Cite journal |last=Habermann |first=A. N. |date=1973 |title=Critical comments on the programming language Pascal |url=http://dx.doi.org/10.1007/bf00288652 |journal=Acta Informatica |volume=3 |issue=1 |pages=47–57 |doi=10.1007/bf00288652 |issn=0001-5903}} ([https://kilthub.cmu.edu/articles/Critical_comments_on_the_programming_language_PASCAL/6604568/files/12094973.pdf full text of technical report])</ref> Later, [[Brian Kernighan]], who popularized the [[C (programming language)|C language]], outlined his criticisms of Pascal in 1981 in his article "Why Pascal is Not My Favorite Programming Language".<ref>Brian W. Kernighan (1981). [http://www.lysator.liu.se/c/bwk-on-pascal.html "Why Pascal is Not My Favorite Programming Language"]. {{webarchive |url=https://web.archive.org/web/20090428163341/https://www.princeton.edu/~mike/unixhistory |date=2009-04-28}}</ref> The most serious problem Kernighan described was that array sizes and string lengths were part of the type, so it was not possible to write a function that would accept variable-length arrays or even strings as parameters. This made it unfeasible to write, for example, a sorting library. Kernighan also criticized the unpredictable order of evaluation of Boolean expressions, poor library support, and lack of [[static variable]]s, and raised a number of smaller issues. Also, he stated that the language did not provide any simple constructs to "escape" (knowingly and forcibly ignore) restrictions and limitations.  More general complaints from other sources<ref name="Hoare.Sneeringer.Welsh.1977"/><ref>{{cite journal |last1=Lecarme |first1=O. |last2=Desjardins |first2=P. |title=More comments on the programming language Pascal |journal=Acta Informatica |date=1975 |volume=4 |issue=3 |pages=231–243 |doi=10.1007/BF00288728}}</ref> noted that the scope of declarations was not clearly defined in the original language definition, which sometimes had serious consequences when using [[forward declaration]]s to define pointer types, or when record declarations led to [[Recursive data type|mutual recursion]], or when an identifier may or may not have been used in an enumeration list. Another difficulty was that, like [[ALGOL 60]], the language did not allow procedures or functions passed as parameters to predefine the expected type of their parameters.

===Rising popularity in the 1970s and 1980s===
In the two decades after 1975, Pascal gained increasing attention and became a major programming language for important platforms (including Apple II, Apple III, Apple Lisa, Commodore systems, Z-80-based machines and IBM PC) due to the availability of UCSD Pascal and Turbo Pascal.<ref>{{cite web |last1=Crespo |first1=Diego |title=Pascal: The language that almost took over the world part 1 |url=https://www.deusinmachina.net/p/pascal-the-language-that-almost-took?utm_source=publication-search |website=www.deusinmachina.net |access-date=4 January 2025 |language=en}}</ref>

Despite initial criticisms, Pascal continued to evolve, and most of Kernighan's points do not apply to versions of the language which were enhanced to be suitable for commercial product development, such as Borland's [[Turbo Pascal]]. As Kernighan predicted in his article, most of the extensions to fix these issues were incompatible from compiler to compiler. Since the early 1990s, however, most of the varieties seem condensed into two categories: ISO and Borland-like. Extended Pascal addresses many of these early criticisms.  It supports variable-length strings, variable initialization, separate compilation, short-circuit Boolean operators, and default (<code>otherwise</code>) clauses for case statements.<ref>{{Cite web |url=http://pascal-central.com/ppl/chapter3.html#Extended |title=Extended Pascal |url-status=dead |archive-url=https://web.archive.org/web/20151018023934/http://www.pascal-central.com/ppl/chapter3.html |archive-date=2015-10-18 |access-date=2015-10-17 }}</ref>

Some of the problems arising from the differences in the implementations of Pascal were later partly solved by the advent of Free Pascal, which supports several dialects with mode directives.<ref>{{cite web |last1=Crespo |first1=Diego |title=Pascal: The language that almost took over the world part 2 |url=https://www.deusinmachina.net/p/pascal-the-language-that-almost-took-56a?utm_source=publication-search |website=www.deusinmachina.net |access-date=4 January 2025 |language=en}}</ref>