2011-08-28 15:59:50 +08:00
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<TeXmacs|1.0.5.2>
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<style|tmdoc>
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<\body>
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<tmdoc-title|Why <TeXmacs> uses <value|scheme> as its extension language>
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At a first glance, the choice of <value|scheme> as an extension language
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for <TeXmacs> may seem a bit strange for people who are accustomed to more
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conventional programming languages, such as <name|C++>, <name|Java>
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or<nbsp><name|Python>. In particular, its heavy use of parenthesis
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frightens more than one person.
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Our choice of <value|scheme> has been motivated by the fact that the
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language is highly flexible in several<nbsp>ways:
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<\enumerate>
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<item>It is easy to mix programs and data in a common framework.
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<item>It is easy to customize the language itself, by adding new
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programming constructs.
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<item>It is easy to write programs on a very abstract level.
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</enumerate>
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The first two features are very particular important for extension
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languages. Indeed, one major use of extension languages is to store data
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for the application (like keyboard shortcuts and menus) in an intelligent
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way. Furthermore, the application usually provides some very typical
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features, which may need to be reflected at the level of the extension
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language.
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For the first two features, the simplicity of the parenthesized notation
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2017-10-13 14:30:48 +08:00
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used by <value|scheme> is also an advantage. Indeed, consider the
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2011-08-28 15:59:50 +08:00
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following fragment of the definition of the <menu|File> menu:
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<\scheme-fragment>
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(menu-bind file-menu
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\ \ ("New" (new-buffer))
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\ \ ("Load" (choose-file load-buffer "Load file" ""))
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\ \ ("Save" (save-buffer))
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\ \ ...)
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</scheme-fragment>
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The entries of the menu (the data) and the corresponding actions (the
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programs) are very readable using the bracket notation. Similarly, when
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defining a new language primitive, the systematic use of the bracket
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notation relieves the user from the burden of making the corresponding
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changes in the parser.
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<tmdoc-copyright|2005|Joris van der Hoeven>
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<tmdoc-license|Permission is granted to copy, distribute and/or modify this
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document under the terms of the GNU Free Documentation License, Version 1.1
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or any later version published by the Free Software Foundation; with no
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Invariant Sections, with no Front-Cover Texts, and with no Back-Cover
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Texts. A copy of the license is included in the section entitled "GNU Free
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Documentation License".>
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</body>
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