Examine individual changes

'{{lowercase}} '''var'aq''' is an [[esoteric programming language]] based on the fictional Klingon language. var'aq was created in 2000 by [[Brian Connors]], with some help from [[Chris Pressey]] and [[Mark Shoulson]]. There are two equivalent sets of instructions for var'aq, one with Klingon keywords and one with English keywords. Most of the instructions in var'aq operate directly on the [[stack]], but there is also a variable space where values and procedures can be stored by name. var'aq supports the following data types: number, function, list and string. ==Using variables== To assign a value to a variable you must first push the value, then the name of the variable onto the stack. To push the name of a variable instead of its value, the spec tells you to use '''lI'moH''' operator. The '''cher''' operator can then be used to bind the value to the variable name. 1 lI'moH var cher (* var = 1 *) However, in the reference interpreter the '''lI'moH''' operator does not work inside a procedure. This is probably a bug, and not intended. As a workaround for this you can push the variable name as a string instead: 1 "var" cher Alternatively you can create a pointer to the variable outside of the procedure: lI'moH var lI'moH pvar cher (* pvar's value is var's name *) { 1 pvar cher } (* pushing pvar will now be equivalent with pushing lI'moH var *) The '''lI'moH''' operator can also be written as '''~'''. ==Examples== ===[[Hello, world!]]=== "Hello, world!" cha' ===[[Fibonacci sequence]]=== This program will display the 20 first Fibonacci numbers. 0 lI'moH A cher (* store the first two numbers as A and B *) 1 lI'moH B cher A cha' B cha' (* print the first two numbers *) 18 { (* repeat 18 times *) A B boq (* push the sum of A and B *) latlh (* duplicate the result *) cha' (* print the new number *) B "A" cher (* store B in A *) "B" cher (* store the new number in B *) } vangqa' (* end repeat *) Note that the '''vangqa'''' keyword does not work in the interpreter available on the var'aq home page, so be sure to use the updated interpreter below! ===[[99 bottles of beer]]=== ~ bottles { latlh 1 rap'a' "" tam { woD "s" } ghobe'chugh " bottle" tam tlheghrar tam woD " of beer" tlheghrar } pong ~ print-verse { latlh latlh bottles tlheghrar " on the wall" tlheghrar cha' latlh latlh bottles tlheghrar cha' "Take one down and pass it around" cha' wa'boqHa' latlh latlh { "No" } ghobe'chugh latlh bottles tlheghrar " on the wall" tlheghrar cha' "" cha' latlh { print-verse } HIja'chugh } pong 99 print-verse ===Leap year=== <nowiki> 'Ij ~ DIS cher (* if it is divisible by 4 but not by 100 *) DIS 4 chuv 0 rap'a' DIS 100 chuv 0 rapbe'a' je (* if it is divisible by 100 and by 400 *) DIS 100 chuv 0 rap'a' DIS 400 chuv 0 rap'a' je (* if any of the above *) joq latlh { "Is a leap year" cha' } HIja'chugh { "Isn't a leap year" cha' } ghobe'chugh </nowiki> ==External resources== * [http://www.reocities.com/connorbd/varaq/index.html var'aq home page] (Reocities) * {{wayback|20091024195817|http://geocities.com/connorbd/varaq/varaq.pl|Perl var'aq interpreter}} - Latest available version, which for some reason is not mentioned on the home page. * [http://www.reocities.com/connorbd/varaq/varaqspec.html var'aq language specification] (Reocities) * [http://en.wikipedia.org/wiki/Klingon_language Wikipedia article about the Klingon language] * [http://web.tampabay.rr.com/ngabwi/varaq.htm Scott Willis' var'aq page] - contains tutorial and code examples. {{deadlink}} * [http://groups.yahoo.com/group/varaq-dev/ var'aq Yahoo! Groups mailinglist] - not very active, but the archive has several posts from the designer [[Category:Languages]] [[Category:Stack-based]] [[Category:Implemented]] [[Category:Functional paradigm]] [[Category:Thematic]] [[Category:Unknown computational class]] [[Category:2000]]'