资料来源 : Free On-Line Dictionary of Computing

visual programming language
     
         (VPL) Any programming language that allows the user
        to specify a program in a two-(or more)-dimensionsional way.
        Conventional textual languages are not considered
        two-dimensional since the {compiler} or {interpreter}
        processes them as one-dimensional streams of characters.  A
        VPL allows programming with visual expressions - spatial
        arrangements of textual and graphical symbols.
     
        VPLs may be further classified, according to the type and
        extent of visual expression used, into {icon}-based languages,
        {form}-based languages and {diagram language}s.  {Visual
        programming environment}s provide graphical or iconic elements
        which can be manipulated by the user in an interactive way
        according to some specific spatial grammar for program
        construction.
     
        A visually transformed language is a non-visual language with
        a superimposed visual representation.  Naturally visual
        languages have an inherent visual expression for which there
        is no obvious textual equivalent.
     
        {Visual Basic}, {Visual C++} and the entire {Microsoft} Visual
        family are not, despite their names, visual programming
        languages.  They are textual languages which use a graphical
        {GUI builder} to make programming interfaces easier.  The user
        interface portion of the programming environment is visual,
        the languages are not.  Because of the confusion caused by the
        multiple meanings of the term "{visual programming}", Fred
        Lakin has proposed the term "executable graphics" as an
        alternative to VPL.
     
        Some examples of visual programming languages are {Prograph},
        {Pict}, {Tinkertoy}, {Fabrik}, {CODE 2.0} and {Hyperpascal}.
     
        {(http://www.cogs.susx.ac.uk/users/ianr/vpl.html)}.
        {(http://cuiwww.unige.ch/eao/www/readme.html)}.
     
        {Usenet} newsgroup: {news:comp.lang.visual} (NOT for {Visual
        Basic} or {Visual C++}).
     
        (1995-02-10)