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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 -- RELATED DOCUMENTATION -- 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 shows: 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 REF * VMCODE 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 ---------------------------------------------- REF *WORDS - on the representation of words in POP-11 REF *IDENT - on the relation between words and identifiers HELP *FULL_IDENTPROPS - gives more information about a word than identprops HELP *IDENTTYPE - gives the type of a variable. HELP *IDENTIFIERS - summary of use and recognition of identifiers in POP-11 HELP *VARS - declaring variables HELP *DLOCAL - making varibles local to a procedure without changing their syntactic properties. Also sets entry and exit actions. HELP *LEXICAL - lexically scoped identifiers HELP *CONSTANT - declaring constants HELP *ACTIVE_VARIABLES - declaring and using 'active' variables REF *SECTIONS - technical information on sections --- C.all/help/identprops ---------------------------------------------- --- Copyright University of Sussex 1987. All rights reserved. ----------