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[[File:Whitespace in vim2.png|right|206px|thumb|Whitespace [[hello world program]] with syntax highlighting {{legend|#0000ab|tabs}} {{legend|#ab0000|spaces}}]] <!-- make SVG file -->
'''Whitespace''' is an [[esoteric programming language|esoteric]] [[programming language]] with [[syntax]] where ''only'' [[whitespace characters]] ([[Space character|space]], [[Tab character|tab]] and [[linefeednewline ]]) have meaning {{endash}} contrasting typical languages that largely ignore whitespace characters.
<ref name="whitespace">{{cite web|url=http://compsoc.dur.ac.uk/whitespace/tutorial.php|title=Whitespace|website=Compsoc|access-date=2015-12-08|url-status=dead|archive-url=https://web.archive.org/web/20150618184706/http://compsoc.dur.ac.uk/whitespace/tutorial.php|archive-date=18 June 2015}}</ref><ref name=parker>{{cite book|title=Humble Pi: a comedy of maths errors|publisher=Allen Lane|date=2019|first=Matt|last=Parker|author-link=Matt Parker|ISBN=978-0-241-36023-1|page=21}}</ref>
== Syntax ==
Whitespace defines a command as a sequencessequence of whitespace characters. For example, <code>[Tab][Space][Space][Space]</code> performs arithmetic addition of the top two elements on the stack.
A command is written as an instruction modification parameter (IMP) followed by an operation and then any parameters.
<code><span style="color:#ffffff;background:#ff9999">space</span></code>,
<code><span style="color:#ffffff;background:#9999ff">tab</span></code>, and <code>linefeed</code>.
{{not a typo start}}
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{{not a typo end}}
When Whitespace source code is displayed in some browsers, the horizontal spacing produced by a tab character is not fixed, but depends on its ___location in the text relative to the next [[Tab key#HTML|horizontal tab stop]]. Depending on the software, tab characters may also get replaced by the corresponding variable number of space characters.
