105 lines
4.0 KiB
C
105 lines
4.0 KiB
C
/*****************************************************************************/
|
|
/* Copyright (C) 2020 NORMAN MEGILL nm at alum.mit.edu */
|
|
/* License terms: GNU General Public License */
|
|
/*****************************************************************************/
|
|
/*34567890123456 (79-character line to adjust editor window) 2345678901234567*/
|
|
|
|
#ifndef METAMATH_MMUNIF_H_
|
|
#define METAMATH_MMUNIF_H_
|
|
|
|
#include "mmdata.h"
|
|
|
|
extern long g_minSubstLen; /* User-settable value - 0 or 1 */
|
|
extern long g_userMaxUnifTrials;
|
|
/* User-defined upper limit (# backtracks) for unification trials */
|
|
extern long g_unifTrialCount;
|
|
/* 0 means don't time out; 1 means start counting trials */
|
|
extern long g_unifTimeouts; /* Number of timeouts so far for this command */
|
|
extern flag g_hentyFilter; /* Turns Henty filter on or off */
|
|
|
|
/* 26-Sep-2010 nm */
|
|
extern flag g_bracketMatchInit; /* So eraseSource() (mmcmds.c) can clr it */
|
|
|
|
/* 1-Oct-2017 nm Made this global so eraseSource() (mmcmds.c) can clr it */
|
|
extern nmbrString *g_firstConst;
|
|
/* 2-Oct-2017 nm Made these global so eraseSource() (mmcmds.c) can clr them */
|
|
extern nmbrString *g_lastConst;
|
|
extern nmbrString *g_oneConst;
|
|
|
|
|
|
nmbrString *makeSubstUnif(flag *newVarFlag,
|
|
nmbrString *trialScheme, pntrString *stateVector);
|
|
|
|
|
|
char unify(
|
|
nmbrString *schemeA,
|
|
nmbrString *schemeB,
|
|
/* nmbrString **unifiedScheme, */ /* stateVector[8] holds this */
|
|
pntrString **stateVector,
|
|
long reEntryFlag);
|
|
/* This function unifies two math token strings, schemeA and
|
|
schemeB. The result is contained in unifiedScheme.
|
|
0 is returned if no assignment is possible.
|
|
If reEntryFlag is 1, the next possible set of assignments, if any,
|
|
is returned. 2 is returned if the unification times out.
|
|
(*stateVector) contains the state of the previous
|
|
call. It is the caller's responsibility to deallocate the
|
|
contents of (*stateVector) when done, UNLESS a 0 is returned.
|
|
The caller must assign (*stateVector) to a legal pntrString
|
|
(e.g. NULL_PNTRSTRING) before calling.
|
|
|
|
All variables with a tokenNum > saveMathTokens are assumed
|
|
to be "unknown" variables that can be assigned; all other
|
|
variables are treated like constants in the unification
|
|
algorithm.
|
|
|
|
The "unknown" variable assignments are contained in (*stateVector)
|
|
(which is a complex structure, described below). Some "unknown"
|
|
variables may have no assignment, in which case they will
|
|
remain "unknown", and others may have assignments which include
|
|
"unknown" variables.
|
|
*/
|
|
|
|
|
|
/* oneDirUnif() is like unify(), except that when reEntryFlag is 1,
|
|
a new unification is returned ONLY if the assignments to the
|
|
variables in schemeA have changed. This is used to speed up the
|
|
program. */
|
|
flag oneDirUnif(
|
|
nmbrString *schemeA,
|
|
nmbrString *schemeB,
|
|
pntrString **stateVector,
|
|
long reEntryFlag);
|
|
|
|
|
|
/* uniqueUnif() is like unify(), but there is no reEntryFlag, and 3 possible
|
|
values are returned:
|
|
0: no unification was possible.
|
|
1: exactly one unification was possible, and stateVector is valid.
|
|
2: unification timed out.
|
|
3: more than one unification was possible. */
|
|
char uniqueUnif(
|
|
nmbrString *schemeA,
|
|
nmbrString *schemeB,
|
|
pntrString **stateVector);
|
|
|
|
/* unifyH() is like unify(), except that when reEntryFlag is 1,
|
|
a new unification is returned ONLY if the normalized unification
|
|
does not previously exist in the "Henty filter". This reduces
|
|
ambiguous unifications. The values returned are the same as
|
|
those returned by unify(). (The elimination of equivalent
|
|
unifications was suggested by Jeremy Henty.) */
|
|
char unifyH(
|
|
nmbrString *schemeA,
|
|
nmbrString *schemeB,
|
|
pntrString **stateVector,
|
|
long reEntryFlag);
|
|
|
|
/* Cleans out a stateVector if not empty */
|
|
void purgeStateVector(pntrString **stateVector);
|
|
|
|
/* Prints the substitutions determined by unify for debugging purposes */
|
|
void printSubst(pntrString *stateVector);
|
|
|
|
#endif /* METAMATH_MMUNIF_H_ */
|