资料来源 : pyDict

向前方,向前

资料来源 : Webster's Revised Unabridged Dictionary (1913)

Forth \Forth\, v.[AS. for[eth], fr. for akin to D. voort, G.
   fort [root]78. See {Fore}, {For}, and cf. {Afford},
   {Further}, adv.]
   1. Forward; onward in time, place, or order; in advance from
      a given point; on to end; as, from that day forth; one,
      two, three, and so forth.

            Lucas was Paul's companion, at the leastway from the
            sixteenth of the Acts forth.          --Tyndale.

            From this time forth, I never will speak word.
                                                  --Shak.

            I repeated the Ave Maria; the inquisitor bad me say
            forth; I said I was taught no more.   --Strype.

   2. Out, as from a state of concealment, retirement,
      confinement, nondevelopment, or the like; out into notice
      or view; as, the plants in spring put forth leaves.

            When winter past, and summer scarce begun, Invites
            them forth to labor in the sun.       --Dryden.

   3. Beyond a (certain) boundary; away; abroad; out.

            I have no mind of feasting forth to-night. --Shak.

   4. Throughly; from beginning to end. [Obs.] --Shak.

   {And so forth}, {Back and forth}, {From forth}. See under
      {And}, {Back}, and {From}.

   {Forth of}, {Forth from}, out of. [Obs.] --Shak.

   {To bring forth}. See under {Bring}.

Forth \Forth\, prep.
   Forth from; out of. [Archaic]

         Some forth their cabins peep.            --Donne.

Forth \Forth\, n. [OE., a ford. ? 78. See {Frith}.]
   A way; a passage or ford. [Obs.] --Todd.

资料来源 : WordNet®

forth
     adv 1: from a particular thing or place or position (`forth' is
            obsolete); "ran away from the lion"; "wanted to get
            away from there"; "sent the children away to boarding
            school"; "the teacher waved the children away from the
            dead animal"; "went off to school"; "they drove off";
            "go forth and preach" [syn: {away}, {off}]
     2: forward in time or order or degree; "from that time forth";
        "from the sixth century onward" [syn: {forward}, {onward}]
     3: out into view; "came forth from the crowd"; "put my ideas
        forth"

资料来源 : Free On-Line Dictionary of Computing

FORTH
     
        1.  An interactive extensible language using
        {postfix syntax} and a data stack, developed by Charles
        H. Moore in the 1960s.  FORTH is highly user-configurable and
        there are many different implementations, the following
        description is of a typical default configuration.
     
        Forth programs are structured as lists of "words" - FORTH's
        term which encompasses language keywords, primitives and
        user-defined {subroutines}.  Forth takes the idea of
        subroutines to an extreme - nearly everything is a subroutine.
        A word is any string of characters except the separator which
        defaults to space.  Numbers are treated specially.  Words are
        read one at a time from the input stream and either executed
        immediately ("interpretive execution") or compiled as part of
        the definition of a new word.
     
        The sequential nature of list execution and the implicit use
        of the data stack (numbers appearing in the lists are pushed
        to the stack as they are encountered) imply postfix syntax.
        Although postfix notation is initially difficult, experienced
        users find it simple and efficient.
     
        Words appearing in executable lists may be "{primitives}"
        (simple {assembly language} operations), names of previously
        compiled procedures or other special words.  A procedure
        definition is introduced by ":" and ended with ";" and is
        compiled as it is read.
     
        Most Forth dialects include the source language structures
        BEGIN-AGAIN, BEGIN-WHILE-REPEAT, BEGIN-UNTIL, DO-LOOP, and
        IF-ELSE-THEN, and others can be added by the user.  These are
        "compiling structures" which may only occur in a procedure
        definition.
     
        FORTH can include in-line {assembly language} between "CODE"
        and "ENDCODE" or similar constructs.  Forth primitives are
        written entirely in {assembly language}, secondaries contain a
        mixture.  In fact code in-lining is the basis of compilation
        in some implementations.
     
        Once assembled, primitives are used exactly like other words.
        A significant difference in behaviour can arise, however, from
        the fact that primitives end with a jump to "NEXT", the entry
        point of some code called the sequencer, whereas
        non-primitives end with the address of the "EXIT" primitive.
        The EXIT code includes the scheduler in some {multi-tasking}
        systems so a process can be {deschedule}d after executing a
        non-primitive, but not after a primitive.
     
        Forth implementations differ widely.  Implementation
        techniques include {threaded code}, dedicated Forth
        processors, {macros} at various levels, or interpreters
        written in another language such as {C}.  Some implementations
        provide {real-time} response, user-defined data structures,
        {multitasking}, {floating-point} arithmetic, and/or {virtual
        memory}.
     
        Some Forth systems support virtual memory without specific
        hardware support like {MMU}s.  However, Forth virtual memory
        is usually only a sort of extended data space and does not
        usually support executable code.
     
        FORTH does not distinguish between {operating system} calls
        and the language.  Commands relating to I/O, {file systems}
        and {virtual memory} are part of the same language as the
        words for arithmetic, memory access, loops, IF statements, and
        the user's application.
     
        Many Forth systems provide user-declared "vocabularies" which
        allow the same word to have different meanings in different
        contexts.  Within one vocabulary, re-defining a word causes
        the previous definition to be hidden from the interpreter (and
        therefore the compiler), but not from previous definitions.
     
        FORTH was first used to guide the telescope at NRAO, Kitt
        Peak.  Moore considered it to be a {fourth-generation
        language} but his {operating system} wouldn't let him use six
        letters in a program name, so FOURTH became FORTH.
     
        Versions include fig-FORTH, FORTH 79 and FORTH 83.
     
        {FAQs
        (http://www.complang.tuwien.ac.at/forth/faq/faq-general-2.html)}.
        {ANS Forth standard, dpANS6
        (http://www.taygeta.com/forth/dpans.html)}.
     
        FORTH Interest Group, Box 1105, San Carlos CA 94070.
     
        See also {51forth}, {F68K}, {cforth}, {E-Forth}, {FORML},
        {TILE Forth}.
     
        [Leo Brodie, "Starting Forth"].
     
        [Leo Brodie, "Thinking Forth"].
     
        [Jack Woehr, "Forth, the New Model"].
     
        [R.G. Loeliger, "Threaded Interpretive Languages"].
     
        2. {FOundation for Research and Technology - Hellas}.
     
        (1997-04-16)