SYMBOL cont_TermMaxVar(CONTEXT Context, TERM Term)
/*********************************************************
INPUT: A context and a term.
RETURNS: The maximal variable in <Term> with respect to
the bindings in <Context>
********************************************************/
{
LIST scan;
SYMBOL result;
#ifdef CHECK
if (!term_IsTerm(Term)) {
misc_StartErrorReport();
misc_ErrorReport("\n In cont_TermMaxVar: Input term is corrupted.\n");
misc_FinishErrorReport();
}
#endif
Term = cont_Deref(&Context,Term);
result = symbol_Null();
if (term_IsStandardVariable(Term)) {
if (term_TopSymbol(Term) > result)
result = term_TopSymbol(Term);
} else {
for (scan = term_ArgumentList(Term); !list_Empty(scan); scan = list_Cdr(scan)) {
SYMBOL max = cont_TermMaxVar(Context, list_Car(scan));
if (max > result)
result = max;
}
}
return result;
}
void cont_BackTrackLastBindingHelp(void)
{
cont_CURRENTBINDING = cont_LastBinding();
cont_SetLastBinding(cont_BindingLink(cont_CURRENTBINDING));
cont_SetBindingTerm(cont_CURRENTBINDING, NULL);
cont_SetBindingContext(cont_CURRENTBINDING, NULL);
cont_SetBindingRenaming(cont_CURRENTBINDING, symbol_Null());
cont_SetBindingLink(cont_CURRENTBINDING, NULL);
cont_BINDINGS--;
}
void cont_InitBinding(CONTEXT C, SYMBOL Var)
/**********************************************************
INPUT: A context and a variable.
RETURNS: Nothing.
EFFECT: Initializes a binding of variable in the
given context.
********************************************************/
{
cont_CURRENTBINDING = cont_Binding(C, Var);
cont_SetBindingLink(cont_CURRENTBINDING, (CONTEXT)NULL);
cont_SetBindingTerm(cont_CURRENTBINDING, (TERM)NULL);
cont_SetBindingSymbol(cont_CURRENTBINDING, Var);
cont_SetBindingRenaming(cont_CURRENTBINDING, symbol_Null());
cont_SetBindingContext(cont_CURRENTBINDING, (CONTEXT)NULL);
}
void symbol_FPrint(FILE* File, SYMBOL Symbol)
/**************************************************************
INPUT: A file and a symbol.
RETURNS: None.
SUMMARY: Prints a symbol to the file.
***************************************************************/
{
#ifdef CHECK
if (!symbol_IsSymbol(Symbol)) {
misc_StartErrorReport();
misc_ErrorReport("\n In symbol_FPrint: Illegal input.\n");
misc_FinishErrorReport();
}
#endif
if (symbol_Equal(symbol_Null(),Symbol))
fputs("NULL", File);
else if (symbol_IsVariable(Symbol)) {
SYMBOL NormSymbol;
NormSymbol = symbol_NormVar(Symbol);
if (symbol_IsStandardVariable(Symbol)) {
if (Symbol <= 6)
/* U, V, W, X, Y, Z */
sprintf(symbol_VARSTRING,"%c", 'U' + NormSymbol - 1);
else
/* X1, X2, X3, ... */
sprintf(symbol_VARSTRING,"X%d", NormSymbol - 6);
}
else if (symbol_IsIndexVariable(Symbol))
/* I1, I2, I3, ... */
sprintf(symbol_VARSTRING,"I%d", NormSymbol);
fputs(symbol_VARSTRING, File);
}
else if (symbol_SignatureExists())
fputs(symbol_Name(Symbol), File);
else
fprintf(File, "%d", Symbol);
}
