Talk:Yacc

Image
What kind of imnage are we looking for? Yacc input? The output? It's a program, what do I tak a picture of? RJFJR 02:44, Jun 17, 2005 (UTC)

Agree. Is a program, no sense to have an image.

Should we site some sources for all the languages it's been ported to? I've neer heard of a Limbo or Ratfor Yacc.

When did the original yacc came out? I think this is something missing in the article. Frigoris (talk) 01:29, 31 October 2008 (UTC)


 * It references the paper by Johnson in 1979 (perhaps older than that, but one cannot tell from the paper itself). Tedickey (talk) 01:59, 31 October 2008 (UTC)

Lowercase for yacc?
Though the title of this article is in lowercase by, I can find that uppercase is used in quite a number of places in the article. Should they be changed to lowercase? --Quest for Truth (talk) 11:13, 30 January 2009 (UTC)


 * probably (though as a stylistic issue, I'd leave a leading cap on sentences) Tedickey (talk) 14:16, 30 January 2009 (UTC)

Implementations in various languages
There's a (growing) list of languages in which yacc is claimed to have been reimplemented. Some are reasonably notable, and can probably be reliably sourced. But the list presently is unsourced. Tedickey (talk) 13:24, 29 March 2009 (UTC)

Most C parsing is no longer Yacc-based
I corrected the original flat statement that C parsers are Yacc-based. There may still be some out there, but as of 28 Feb 2006, the all-important GCC frontend is not generated by Yacc or any tool derived from Yacc -- it's a hand-written recursive descent parser.

I also added a citation needed. We need a reference to show that the original AT&T/K&R C compilers were Yacc-based. (Was the first UNIX C compiler YACC based? I think so, but I'm not sure.)  To see that as of 4.1, GCC is not YACC-based, there is this reference -- it's long but searchable. Look for this statement: "The old Bison-based C and Objective-C parser has been replaced by a new, faster hand-written recursive-descent parser." —Preceding unsigned comment added by Jeffreykegler (talk • contribs) 00:26, 14 September 2010 (UTC)


 * Dennis Ritchie's C parser (the original) in V7 was not yacc-based, however Stephen Johnson's C parser was. Ken Thompson's later Plan9 and Go C parsers are yacc-based. Thompson's love of yacc is well known. 70.225.161.132 (talk) 21:34, 3 April 2011 (UTC)


 * See also the Red Dragon Book pp. 375 ff. for a discussion of the Unix compiler and PCC. 70.225.161.132 (talk) 00:21, 10 April 2011 (UTC)

interesting, but not supporting the statement
The abstract for the paper doesn't come close to promising that it supports the original research constructed here in a recent edit TEDickey (talk) 16:55, 1 January 2018 (UTC)


 * 1. It's not clear which "original research" you are referring to?
 * 2. The cited paper does show more modern approach to parsing than YACC
 * 3. The main issue I see here is that the introductory statement is immediately undermined by "citation needed". The lay reader has no idea that (a) Linux is the de-facto modern unix and (b) linux distributions do not use YACC (they instead supply BISON)
 * 4. How can we edit the introductory statement to make this clear without having the (undermining) 'citation needed' and having to explain the whole history of linux vs unix, FOSS etc?

In "Flex & Bison" (O'Reilly, 2009) the author states (about Corbett's YACC variant) "Since his version was faster than Bell’s yacc and was distributed under the flexible Berkeley license, it quickly became the most popular version of yacc.". Perhaps this is the source of the statement? — Preceding unsigned comment added by Psychoceramicist (talk • contribs) 18:00, 1 January 2018 (UTC)


 * This is original research: citing a paper which talks about different tools, which likely are not installed on a given system to support the point of the overall sentence which is in the final clause "though it has since been supplanted[2][discuss] as the default by more recent, largely compatible, programs." A couple of (independent, relevant) sources would be suitable.  Beyond the interesting title, the abstract says the paper is not relevant to this topic. TEDickey (talk) 01:23, 2 January 2018 (UTC)

I've added two references, removed the 'yacc is dead' reference, and made the language more encyclopaedic. Do you still see original research? Psychoceramicist (talk) 08:07, 2 January 2018 (UTC)

This article appears to be about AT&T Yacc
There are several articles about different versions of Yacc in wikipedia. This one appears to be about the (original) AT&T Yacc.


 * 1) Should it be renamed?
 * 2) Should the separate articles be merged? They have much more in common than they have differences?

Psychoceramicist (talk) 17:17, 2 January 2018 (UTC)


 * There's a template and guidelines for soliciting discussion on suggested merges. Start here: "Template:Merge" TEDickey (talk) 02:10, 3 January 2018 (UTC)

undue weight in "Impact"
A recent promotional edit reused a single sentence from The Unix Programming Environment (chapter 8, page 287), which reads "yacc, and to a lesser degress lex, have been used to implement many language processors, including the portable C compiler, Pascal, FORTRAN 77, Ratfor, awk, bc, eqn, and pic."

Actually, Wikipedia topics should summarize, cite appropriately. This edit didn't do that. TEDickey (talk) 15:29, 29 February 2020 (UTC)
 * I didn't intend to promote Yacc in any way. I meant only to illustrate what languages were built with Yacc. Because previously, before I added mention of AWK, there were no mentions at all of what Yacc was used for.
 * I do agree that the sentence: Programming language hoc was used to demonstrate how to build interpreters using Yacc. – can be deleted, as it's not "Impact" at all. --Amakuha (talk) 11:18, 1 March 2020 (UTC)

Still, a loose paraphrase of a single sentence (not clearly indicated in the citation) doesn't do much except mislead the reader, who is led to suppose that there are numerous mentions to support this. TEDickey (talk) 11:43, 1 March 2020 (UTC)
 * Oh, I see. I actually wrote the sentence based on A Research Unix reader: annotated excerpts from the Programmer's Manual, 1971–1986 (1987) by Doug McIlroy. That source actually mentions more languages, that were built with Yacc, and I mentioned only the ones that are more or less famous. I didn't know that a similar sentence is also found in The Unix Programming Environment.
 * Now that you found a second source, it's closer to "numerous mentions". --Amakuha (talk) 13:20, 1 March 2020 (UTC)

No one's going to agree that two is numerous (actually the second one is likely the original source which the first had in mind, and each citation needs a page number, since the sources aren't mainly about yacc). Keep in mind that the first source gave no supporting sources; it was an offhand comment TEDickey (talk) 13:27, 1 March 2020 (UTC)