View source for ColorForth

{{Short description|Programming language}}
{{Refimprove|article|date=August 2007}}
{{lowercase|title=colorForth}}
{{ infobox programming language
| name            = <span style="color:red;">color</span><span style="color:green;">Forth</span>
| logo            =
| paradigm        = [[Procedural programming|Procedural]], [[stack-oriented programming language|stack-oriented]]
| year            = 1990s
| designer        = [[Charles H. Moore]]
| developer       = [[Charles H. Moore]]
| latest_release_version = {{start date and age|2001|7|31}}<ref name="status">{{cite web
 | url=https://colorforth.github.io/status.html
 | title=colorForth Status
 | date=September 2002
 | archiveurl=https://web.archive.org/web/20160310135832/http://colorforth.com/status.html
 | archivedate=2016-03-10
 | url-status=dead
 }}</ref>
| typing          = Typeless
| dialects        = 
| implementations =
| influenced_by   = [[Forth (programming language)|Forth]]
| influenced      = 
| license = [[Public domain]]<ref name=status/>
| website = Archived at {{URL|https://colorforth.github.io/}}
| file_ext =
}}
'''<span style="color:red;">color</span><span style="color:green;">Forth</span>''' is a [[programming language]] from the [[Forth (programming language)|Forth]] language's creator, [[Charles H.&nbsp;Moore]], developed in the 1990s. The language combines elements of Moore's earlier Forth systems and adds color as a way of indicating how words should be interpreted. Program text is tokenized as it is edited; the compiler operates on the tokenized form, so there is less work at compile time.

<span style="color:red;">color</span><span style="color:green;">Forth</span> is an idiosyncratic programming environment: the colors simplify Forth's semantics, speed compiling, and are said to aid Moore's own poor eyesight: colorForth uses different colors in its source code (replacing some of the punctuation in standard Forth) to determine how different words are treated.

<span style="color:red;">color</span><span style="color:green;">Forth</span> was originally developed as the scripting language for Moore's own [[VLSI]] [[CAD]] program, OKAD,<ref>{{cite web
| url=http://www.ultratechnology.com/okad2.htm
| title=OKAD II (Oh CAD Two)
| date=2001-07-01
| accessdate=2017-06-08}}</ref> with which he develops custom Forth processors. As the language gained utility, he rewrote his CAD program in it, spruced up the environment, and released it to the public. It has since gained a small following, spurred much debate in the Forth community, and sprung offshoots for other processors and operating environments. The language's roots are closer to the Forth machine languages Moore develops for his processors than to the mainstream standardized Forths in more widespread use.

The language comes with its own tiny (63&nbsp;KB) [[operating system]]. Practically everything is stored as source code and compiled when needed. The current{{when?|date=December 2023}} <span style="color:red;">color</span><span style="color:green;">Forth</span> environment is limited to running on [[Pentium compatible processor|Pentium]]-grade PCs with limited support for lowest-common-denominator motherboards, AGP video, disk, and network hardware.

Coloring in <span style="color:red;">color</span><span style="color:green;">Forth</span> has semantic meaning. Red words start a definition, and green words are compiled into the current definition. Thus, <span style="color:red;">color</span><span style="color:green;">Forth</span> would be written in standard Forth as
 : color forth ;

Yellow words are executed. The transition from green to yellow and back again can be used while defining words, to transition between compiling words into the current definition, executing words immediately (manipulating the data stack during compilation), and back again (adding the top of the data stack to the current definition){{snd}} in other words, precomputing a value during compilation (a functionality that other languages use macros or optimizing compilers for).<ref name="wordformat">{{cite web
 | url=http://www.colorforth.com/parsed.html
 | title=PreParsed Word Format
 | website = colorforth.com
 | date=December 2001
 | archiveurl=https://web.archive.org/web/20110906081208/http://www.colorforth.com/parsed.html
 | archivedate=2011-09-06
 | url-status=dead
 }}</ref>

Moore developed Forth in the early 1970s and created a series of implementations of the language. In the 1980s he diverged from the standardization of the language, instead continuing to evolve it. He developed a series of Forth-like languages, each extreme in its simplicity: Machine Forth, OKAD, and <span style="color:red;">color</span><span style="color:green;">Forth</span>.

Moore has stated that color is only one option for displaying the language.{{Citation needed|date=October 2019}} One of Moore's papers{{which?|date=December 2023}} on <span style="color:red;">color</span><span style="color:green;">Forth</span> was printed in black and white but used italics and other typographical conventions to present source code.

== References ==
{{Reflist}}

== External links ==
* {{cite web
| url=http://www.strangegizmo.com/forth/ColorForth/
| title=ColorForth Mail List Archive
| author=Michael Alyn Miller}}
* {{cite web
| url=http://www.ultratechnology.com/forth0.htm#mf
| title=Forth Software and Hardware by Date: Machine Forth and colorForth
| date=2006-04-17
| publisher=UltraTechnology}}
* {{cite web
| url=http://www.inventio.co.uk/cfdos.htm
| title=colorForth downloader
| date=2016-05-24
| author=Howerd Oakford}}
* {{cite web
| url=http://cflinks.strangegizmo.com/
| title=colorForth Resources
| date=2003-08-11}}
* {{SourceForge|colorforth|colorForth code repository and joint development effort}}
* {{Webarchive
| url=https://web.archive.org/web/20140116175425/http://forthworks.com/c4th/doku.php
| title=ColorForth Community Wiki
| date=2014-01-16}}
* {{cite web
| url=http://www.greenarraychips.com/home/documents/greg/cf-intro.htm
| title=Introduction to arrayForth™
| author=Greg Bailey}}

[[Category:Concatenative programming languages]]
[[Category:Experimental programming languages]]
[[Category:Forth programming language family]]
[[Category:Forth implementations]]