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The "logo" listed on this page is actually scanned from a 1940s ad for the [Mercury (automobile)|Ford Mecury]. It's not the logo of the programming language project. --De Guerre05:43, 8 April 2007 (UTC)[reply]

Irregardless its origin, they do seem to be using the picture as their logo. Its alt-Tag also says "[Mercury Logo]" on the web-page.—Precedingunsigned comment added by78.48.165.159 (talk)18:00, 12 February 2008 (UTC)[reply]

As the poster above mentioned, the picture is the official logo as displayed on their website.4zimuth (talk)19:51, 17 February 2008 (UTC)[reply]

I'm afraid I can't counter that due to theWP:NOR rule, but back in the day, I was in the office next to the guy who scanned the picture and put it on the official web page. --De Guerre (talk)23:08, 17 February 2008 (UTC)[reply]

You are probably right about the source of the image but the fact that it appears on the language's main page means that the mercury project has chosen it as their logo and it is fair use for us to use it in the article to identify is as such. Please correct me if I am wrong.4zimuth (talk)03:57, 19 February 2008 (UTC)[reply]

The article could use a few more examples to illustrate Mercury's syntax. If anyone has any ideas on example programs that illustrate Mercury's functional/logical nature please post them. For now I'll add the Fibonacci numbers program from Ralph Becket's tutorial.4zimuth (talk)20:00, 17 February 2008 (UTC)[reply]

Image:Mercury (programming language) logo.jpg is being used on this article. I notice the image page specifies that the image is being used underfair use but there is noexplanation or rationale as to why its use inthis Wikipedia article constitutes fair use. In addition to theboilerplate fair use template, you must also write out on the image description page a specific explanation or rationale for why using this image in each article is consistent withfair use.

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BetacommandBot (talk)14:43, 8 March 2008 (UTC)[reply]

"can make certain programming constructs (such as a switch over a number of options, with a default) harder to express"

Prolog:

(    Day = saturday, !, OpenHours = (8 - 15) ;    Day = sunday, !, OpenHours = (9 - 13) ;    OpenHours = (8 - 17))

Mercury: For the same amount of compiler checking as the above, one could use an if-then-else structure:

( if Day = saturday then      OpenHours = (8 - 15)  else if Day = sunday then      OpenHours = (9 - 13)  else      OpenHours = (8 - 17)).

[Actually, for the above simple example one would probably use the functional form of if-then-else, i.e. OpenHours = ( if ... then (8 - 15) else if ... then (9 - 13) else (8 - 17) ).]

The above doesn't seem a good example of extra difficulty. I'm sure there better examples (maybe failure-driven I/O ?); can someone supply one?—Precedingunsigned comment added byPjrm (talk •contribs)12:04, 1 February 2009 (UTC)[reply]

My guess is that something like this Prolog code might have been meant:

day_openhours(saturday,  8-15) :- !.day_openhours(sunday,    9-13) :- !.day_openhours(_OtherDay, 8-17).  % possibly add a check that the first argument is in fact a day

It's not very pretty, but it gets the job done, is deterministic, and is friendly to clause indexing (i.e., it can possibly compile to smart code that's more efficient than an if-else cascade). Without the cuts, the "default" rule would have to contain some kind of "not one of the days above" condition. That would mean more---redundant!---code, which might justify the "harder to express" judgement.77.117.184.155 (talk)19:04, 2 December 2009 (UTC)[reply]

I find the Prolog construct cuts-in-all-cases-except-the-last more readable than the Mercury equivalent. But that's just my opinion which of course falls foul ofWP:OR. But there is no issue of expressiveness. The claim "harder to express" needs removing or a reliable source.pgr94 (talk)10:57, 3 December 2009 (UTC)[reply]

Mercury: What you really want is something like this:

(   Day = saturday,   OpenHours = (8 - 15);   Day = sunday,   OpenHours = (9 - 13);   ( Day = monday   ; Day = tuesday   ; Day = wednesday   ; Day = thursday   ; Day = friday   ),   OpenHours = (8 - 17)).

This is a switch whose third case is a multi-cons-id case, This gets compiled efficiently, expresses the computation clearly and (in the right context) uses the determinism checker to ensure that all days are covered exactly once. It can also be run in reverse where the OpenHours is ground and Day is free, where it would be nondeterministic.—Precedingunsigned comment added by210.84.17.212 (talk)01:56, 12 February 2010 (UTC)[reply]

It sounds a bit iffy to say that it's designed with "good" software engineering principles. This sounds like it's claiming that compiled, static-typed languages are always better than interpreted, dynamic-typed languages. -Qeny (talk)00:40, 30 April 2009 (UTC)[reply]

Nothing (other than their inescapable humanity) prevents a computer programmer from employing good software engineering principles without the help of a strong static type system. However, for those of us that would rather have help, these guys have 'designed' the language with good 'software engineering principles' in mind. I do not think the word 'good' is strong enough to imply exclusion anyhow. Good does not mean better.— Precedingunsigned comment added by173.191.159.38 (talk)02:06, 8 October 2012 (UTC)[reply]

The website seems to be down more often that it is up (4 out of 5 attempts failed this month). The website looks dated and lacklustre. The forums/mailing lists are full of spam. Shame really, because it looks like an interesting language.pgr94 (talk)14:51, 26 February 2010 (UTC)[reply]

The current stable version dates from 2006 and the compiler does not compile with recent versions ofgcc as supplied with modern linux distributions.[1]pgr94 (talk)06:19, 27 February 2010 (UTC)[reply]

The project is definitely not dead, Melbourne Uni has at least a dozen postgrad + final year undergrad + staff working on the compiler, however i've been told by some friends working on the compiler that it is very difficult (read: impossible) to bootstrap as chunks of the build process assume that a working mercury implementation is available.—Precedingunsigned comment added by131.170.170.135 (talk)05:36, 13 May 2010 (UTC)[reply]

Bootstrapping is really easy and works on any recent Linux, Windows or MacOS X System, please see:README.bootstrap for bootstrapping instructions.Sebgod (talk)09:41, 26 April 2014 (UTC)[reply]

Now (2013), three years later has there been any progress?— Precedingunsigned comment added by78.54.98.110 (talk)19:56, 14 June 2013 (UTC)[reply]

Looks likethe project has moved, which may explain why the old website hasn't been updated.De Guerre (talk)06:59, 10 July 2013 (UTC)[reply]

Yes, the project moved as no-one at the University was currently working on it (we all left the University). No it's not dead, although with only a handful of active developers development can be slow. Mercury is also used, and supported, commercially. (PaulBone (talk)02:51, 29 October 2014 (UTC))[reply]

Both the official website and the wikipedia page claim a daily snapshot, but the latest snapshot was built September 3rd, which at the time this was written was well over a month ago. This cannot be accurately classified as a daily snapshot.— Precedingunsigned comment added by173.191.159.38 (talk)23:03, 7 October 2012 (UTC)[reply]

The way this article reads it's like someone wrote a puff piece for Mercury and someone else wrote margin notes with arrows pointing to circled text defensively saying "BUT PROLOG CAN DO THIS TOO!". This makes Wikipedia look like its editors belong on the short bus.—Precedingunsigned comment added by66.249.20.178 (talk)07:39, 31 December 2010 (UTC)[reply]

Um, no, it really doesn't seem that way at all. I think you are projecting a little. How is that short bus treating you?— Precedingunsigned comment added by86.141.142.230 (talk)20:30, 24 April 2012 (UTC)[reply]

Looks OK to me. The language is a descendant of Prolog, it's unsuprising that it mentions it, and I'm not seeing 'but prolog can do this too'. Maybe this comment's out of date.Anniepoo (talk)00:00, 30 March 2017 (UTC)[reply]

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