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HELP IDENTPROPS                                        A.Sloman Nov 1986

    identprops(<word or identifier>) -> syntactic_type

IDENTPROPS takes a word or identifier as argument, and returns its
syntactic type. For full technical details see REF *IDENT.

CONTENTS - (Use <ENTER> g to access sections)
 -- Introduction
 -- Possible results of IDENTPROPS are
 -- Discovering the identprops of a word in VED
 -- Assigning identprops

-- Introduction -------------------------------------------------------

The POP-11 system does not treat all words alike when compiling.
For example

    vars x;  3 -> x;

is permissible, whilst

    vars if;  3 -> if;

is not. This is because IF is a 'syntax' word, as a call of IDENTPROPS

    identprops("if") =>
    ** syntax

-- Possible results of IDENTPROPS are --------------------------------
- "undef"
    for a word not declared as a permanent identifier (though it may
    have been used as a lexical identifier).

- 0
    for a 'normal' (untyped) identifier (e.g. HD, TL, POPPROMPT etc)

- N (An integer)
    For a POP-11 operator of precendence N, where N is an integer or
    floating-point in the range -12.7 to 12.7 . Examples of standard
    POP-11 operators are:
        = (N=7),  + (N=5),  * (N=4),  div (N=2),  <> (N=5),  :: (N=4)
    (For more examples see HELP * SYSWORDS)

- "syntax"
    For an ordinary syntax word (e.g. if, and, define etc)

- "syntax N" (N an integer)
    For syntactic operators of precedence N. (This sort of word including
    a space cannot be typed in directly to POP-11 but can be constructed
    using *CONSWORD.) Examples of syntactic operators are "(", ".",
    "->", ":"

- "macro"
    For POP-11 macros. See HELP * MACROS, REF * PROGLIST

-- Discovering the identprops of a word in VED ------------------------
The easiest way to find out about the identprops of a POP-11 identifier
is to place the VED cursor immediately to its left then do
    <ENTER> wtype

-- Assigning identprops -----------------------------------------------
The IDENTPROPS of user-defined identifiers may be defined using
*VARS *CONSTANT *DEFINE, or the virtual machine instructions defined in

The identprops of a word is actually the identprops of the identifier
currently associated with it, and that can change from one section to
another, as explained in HELP * IDENTIFIERS and HELP *SECTIONS

-- RELATED DOCUMENTATION ----------------------------------------------
    - on the representation of words in POP-11
    - on the relation between words and identifiers
    - gives more information about a word than identprops
    - gives the type of a variable.
    - summary of use and recognition of identifiers in POP-11
    - declaring variables
    - making varibles local to a procedure without changing their
    syntactic properties. Also sets entry and exit actions.
    - lexically scoped identifiers
    - declaring constants
    - declaring and using 'active' variables
    - technical information on sections

--- C.all/help/identprops ----------------------------------------------
--- Copyright University of Sussex 1987. All rights reserved. ----------