http://snippets.dzone.com/posts Thu, 24 Jul 2008 04:39:41 GMT DZone Snippets: define code http://snippets.dzone.com/posts/show/1151 <code> <br />REBOL [ <br /> Title: "#define dialected function" <br /> File: %define-dialect.r <br /> Author: "Gregg Irwin" <br /> Version: 0.0.1 <br /> Date: 23-sep-2003 <br /> Purpose: { <br /> Make it easier to map C #define statements. Eliminates <br /> the need to manually call datatype conversion functions <br /> for each item. <br /> } <br /> Comment: { <br /> The block you pass to the function is a dialect. In the <br /> dialect you can specify word-value pairs and functions <br /> used to map different types of values as they are <br /> processed. <br /> <br /> MAP is used to tell the processor what function to call <br /> when it encounters a particular datatype value. The <br /> function specified should take a single value. <br /> <br /> 'map datatype function-name <br /> <br /> ; call to-integer when a binary! value is found. <br /> [map binary! to-integer] <br /> <br /> Other than that, just specify a word followed by a value. <br /> The resulting block will contain set-word! values for <br /> each word, followed by its value - which may have been <br /> converted by a function that was mapped to its original <br /> datatype. <br /> } <br /> Example: { <br /> do define [ <br /> map binary! to-integer <br /> map issue! to-integer <br /> <br /> my-name "Gregg" <br /> mapped-binary #{00000001} <br /> mapped-issue #000fffff <br /> ] <br /> print [my-name mapped-binary mapped-issue] <br /> } <br /> library: [ <br /> level: 'intermediate <br /> platform: 'all <br /> type: [function] <br /> domain: [dialect parse external-library] <br /> tested-under: [view 1.2.8.3.1 on W2K] <br /> support: none <br /> license: none <br /> see-also: none <br /> ] <br />] <br /> <br /> <br />define: func [ <br /> block [any-block!] <br /> /local type fn word val result map <br />] [ <br /> result: make block length? block <br /> map: copy [] <br /> either parse block [ <br /> some [ <br /> 'map set type word! set fn word! ( <br /> type: do type <br /> either word: find/skip map type 2 [ <br /> change next word get fn <br /> ][ <br /> append map reduce [type get fn] <br /> ] <br /> ) <br /> | set word any-word! set val any-type! ( <br /> append result reduce [ <br /> to set-word! word <br /> either fn: select map type? val [fn val][val] <br /> ] <br /> ) <br /> ] <br /> to end <br /> ] [result][none] <br />] <br /> <br /> <br />comment [ ; test examples <br /> print mold defs: define [ <br /> map binary! to-integer <br /> map issue! to-integer <br /> <br /> PFD_DOUBLEBUFFER #{00000001} <br /> PFD_STEREO #{00000002} <br /> PFD_DRAW_TO_WINDOW #00000004 <br /> GL_ALL_ATTRIB_BITS #000fffff <br /> ] <br /> do defs <br /> print [ <br /> PFD_DOUBLEBUFFER <br /> PFD_STEREO <br /> PFD_DRAW_TO_WINDOW <br /> GL_ALL_ATTRIB_BITS <br /> ] <br /> <br /> halt <br />] <br /></code> Fri, 13 Jan 2006 04:20:44 GMT http://snippets.dzone.com/posts/show/1151 gregg.irwin (Gregg Irwin)