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         Lesson 7 Part 030 F-PC 3.5 Tutorial by Jack Brown 
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             Quick Review of Some Dictionary Words   
           

 HIDE   ( -- )     Removes last word defined by unlinking it from its
                   vocabulary thread.  Previously smudge bit was set.

 REVEAL ( -- )     Link the most recently defined word into the current
                   vocabulary.  Previously smudge bit was cleared.

 IMMEDIATE ( -- )  Turn on the precedence bit of the most recently
                   defined word in the dictionary. IMMEDIATE  flags a
                   definition so that it is executed during compilation
                   instead of being compiled. Many compiler words are
                   IMMEDIATE.

 '   {word} ( -- cfa ) Leave code field address of {word}. on the stack.

 ['] {word} ( -- cfa ) This is an IMMEDIATE word used within a
            definition. ['] is used to compile the cfa of the following
            word as a LITERAL or number.

 [']        is equivalent to the sequence     [ ' {word} ] LITERAL
            within a colon definition.


DP      ( -- addr ) Variable containing pointer to the first available
                    location in the dictionary.

HERE    ( -- addr ) Returns pointer to end of dictionary as stored in DP


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                     Vocabulary Access Words  
                   

ORDER     ( -- )    Display the CONTEXT vocabulary names forming the
                    search order in their present search order sequence.
                    Then show CURRENT vocabulary into which new
                    definitions will be put. This information is obtained
                    from the CONTEXT and CURRENT below.

CURRENT ( -- addr ) Variable containing the pfa of the vocabulary in to
                    which new definitions are compiled.

CONTEXT ( -- addr ) The address of the array that specifies the search
                    order.

VOCS      ( -- )    List all vocabularies that exist in this FORTH
                    system.

DEFINITIONS ( -- )  Select the first vocabulary in the search path as
                    the compilation vocabulary into which all subsequent
                    new word definitions will be placed.

VOCABULARY  {name}  ( -- )  Make a new VOCABULARY .
                A dictionary entry for {name} is created which specifies
                a new list of word definitions. Subsequent execution of
                {name} replaces the first vocabulary in the current
                search order with {name}. When name becomes the
                compilation vocabulary new definitions will be appended
                to {name}'s word list.

ALSO     ( -- ) Duplicate first context vocabulary making two copies of
                it in the vocabulary the search order.

PREVIOUS ( -- ) The inverse of ALSO, removes the most recently
                referenced vocabulary from the search order.


ROOT  ( -- )    A small vocabulary for controlling search order.

ONLY  ( -- )    Erases the search order and forces the ROOT vocabulary
                to be the first and last.

SEAL  ( -- )    Usage: SEAL FORTH will change the search order such that
                only FORTH will be searched. Used for turn-key
                applications.

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  Please Move to Lesson 7 Part 040 


