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ASSIGNMENTS

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ASSIGNMENT directives are used to set the switches and counters which control compilation and parsing. Switches may have the value TRUE (T), or FALSE (F), while counters may take on any non-negative integer value. Integers may not be assigned to switches, nor may the values TRUE and FALSE be assigned to counters. Switch and counter settings remain in effect until a new value is assigned. The general form of a switch assignment is      *SWITCH=T or      *SWITCH=F The switches in the compiler and parser are: DRAWSW if TRUE, a graphical form of the parse tree is printed after each successful parse. If the tree is too wide to fit on the output device (as determined by the value of LWIDTH), it will be automatically split into smaller trees for printing. Initially FALSE. FULLTRACE if FALSE, operators inside of a routine are not printed when a restriction or transformation is traced. If TRUE, all operators are shown in the trace. (Applicable only to parser). Initially FALSE. FULLTREE if TRUE, each node in a parse tree is assigned a separate line in the parse tree print-out. (Applicable only to parser). Initially FALSE. HOUSE if TRUE, a housing directory is printed at the conclusion of link-editing. This directory shows which restrictions are housed on each element and option of each definition. Any assignment to HOUSE must precede the *LKED() directive; otherwise it will have no effect. Initially FALSE. LXTRAC if TRUE, the lexical scanner prints out for each word its entry in array SENTE [a table in the lexical scanner] and a list of all the lexical types it has been assigned. (Applicable only to compiler). Initially FALSE. MATPRT if TRUE, a message is printed each time something is added to the sublist of a minword attribute (MAT). These messages appear immediately after the tree print-outs for each parse. (Applies to parser). Initially FALSE. OBJSW if TRUE, the generated object grammar is written onto file lun=2 (logical unit number 2). If a new grammar is to be written, an *OBJSW=T directive should precede the first statement in the source file. (Applicable only to compiler). Initially FALSE. OPRINT if TRUE, the generated object grammar is printed out in lithp format after each statement is parsed. (Applicable only to compiler). Initially FALSE. PUTTRC if TRUE, a one-line message is printed for each word written into the object grammar buffer by a generator. (Applicable only to compiler). Initially FALSE. RECURTRACE if TRUE, a two-line message is printed for each call to RECUR, the routine in the parser which handles the recursive mechanism. Initially FALSE. STREAM controls the function of the WRITE operation in restrictions and transformations. If FALSE, each type of item occupies a fixed number of columns, and writing continues on a line until a WRITE END-OF-LINE command is given. If TRUE, each item occupies only as many columns as the individual item requires, and writing continues automatically on the next line when one line is complete. (Applies only to parser). Initially FALSE. TRACE if TRUE, a trace is printed of all nodes attached and detached during a parse, together with the names of all restrictions executed and an indication of whether they succeeded or failed. Initially FALSE. TRACER if TRUE, a trace is printed of all restrictions executed during parsing, showing all operators and whether they succeeded or failed. (Applies to parser only). Initially FALSE. TREESW if TRUE, a linearized form of the parse tree is printed out after each successful parse. If FULLTREE is FALSE (the default value), only strings (node on the STRING list) and their elements will be displayed; intermediate levels in the tree are surpressed. Initially FALSE. TSTTRC if TRUE, a one line message is printed for each generator invoked during parsing. (Applicable only to compiler). Initially FALSE. VERBOS if TRUE, the time required for the parse, the number of nodes in the final tree, and the total number of nodes used are printed after each parse. Initially FALSE. WFFTRACE if TRUE, a one line message is printed each time a wellformedness restriction fails. (Applicable only to parser). Initially FALSE. XDRAWSW if TRUE, a graphical form of the decomposition tree is printed after each successful transformational decomposition (see also DRAWSW). Initially FALSE. XON if TRUE, the transformations are executed after each parse. (Applicable only to parser). Initially FALSE. XREF if TRUE, the data required for generating symbol and literal reference tables for the grammar is written on lun=2 (logical unit number 2). This data can be formatted into tables suitable for printing by one of the print utility programs. An assignment to XREF must precede the *LKED() directive; otherwise it will have no effect. Initially FALSE. XTRACE if TRUE, a trace is printed during the transformational phase showing the name of each transformation executed, and whether it transformed the tree, succeeded, or failed. (Applicable only to parser). Initially FALSE. XTRACER if TRUE, a trace is printed of all transformations, showing all operators and whether they succeeded or failed. (Applies to parser only). Initially FALSE. XTREESW if TRUE, a linearized form of the decomposition tree is printed after each successful transformational decomposition (see also TREESW). (Applies to parser only). Initially FALSE. In addition to the switches listed above, each BNF definition and each restriction has a few switches of its own. These switches are set by a qualified switch assignment, of the form      *SWITCH(SYMBOL)=T or      *SWITCH(SYMBOL)=F where SYMBOL is the name of the definition or restriction. Qualified switch assignments can be used only in the parser and must appear after the *ENGLISH directive. The switches associated with each BNF definition are: COMPLETION if TRUE, each time a node corresponding to this BNF definition is completed the message      NODE --- COMPLETED SUBSUMING (followed by the words subsumed by this node) is printed. For example,      *COMPLETION(ASSERTION)=T will print a message each time an ASSERTION is completed. Initially FALSE. The switches associated with each restriction and transformation are: IGNORE if TRUE, the restriction will be totally ignored. Initially FALSE. TRACER if TRUE, each time this restriction or transformation is executed a trace will be printed showing all operators and whether they succeeded or failed. For example,      *TRACER(WAGREE)=T will cause restriction WAGREE to be traced. A restriction / transformation will be traced if either the [overall] TRACER / XTRACER switch or the individual switch for the restriction is TRUE. Initially FALSE . The general form of a counter assignment is      *COUNTER=INTEGER with no embedded blanks. The counters in the parser are: LINLIM maximum number of lines of output which will be generated during the parsing of a statement (parsing terminates when this limit is reached). Initially 2000. LWIDTH maximum width, in columns, of printed traces and trees. Initially 86, maximum allowed value is 120. NODLIM maximum number of nodes which may be attached during all parses of a statement. (Parsing terminates when this limit is reached). Initially 100000. PARLIM maximum number of parses which will be attempted for each statement. Initially 99.