LemonJS/lemon-src/lempar.js

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2019-01-28 12:08:59 +00:00
/*
** 2000-05-29
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
** Based on SQLite distribution v3.17.0
** Adopted for JavaScript by Artem Butusov <art.sormy@gmail.com>
**
*************************************************************************
** Driver template for the LEMON parser generator.
**
** The "lemon" program processes an LALR(1) input grammar file, then uses
** this template to construct a parser. The "lemon" program inserts text
** at each "%%" line. Also, any "P-a-r-s-e" identifer prefix (without the
** interstitial "-" characters) contained in this template is changed into
** the value of the %name directive from the grammar. Otherwise, the content
** of this template is copied straight through into the generate parser
** source file.
**
** The following is the concatenation of all %include directives from the
** input grammar file:
*/
/************ Begin %include sections from the grammar ************************/
%%
/**************** End of %include directives **********************************/
function Parse() {
/* These constants specify the various numeric values for terminal symbols
** in a format understandable to "makeheaders".
***************** Begin makeheaders token definitions *************************/
%%
/**************** End makeheaders token definitions ***************************/
/* The next sections is a series of control #defines.
** various aspects of the generated parser.
** YYNOCODE is a number of type YYCODETYPE that is not used for
** any terminal or nonterminal symbol.
** YYFALLBACK If defined, this indicates that one or more tokens
** (also known as: "terminal symbols") have fall-back
** values which should be used if the original symbol
** would not parse. This permits keywords to sometimes
** be used as identifiers, for example.
** YYSTACKDEPTH is the maximum depth of the parser's stack. If
** zero the stack is dynamically sized using realloc()
** YYERRORSYMBOL is the code number of the error symbol. If not
** defined, then do no error processing.
** YYNSTATE the combined number of states.
** YYNRULE the number of rules in the grammar
** YY_MAX_SHIFT Maximum value for shift actions
** YY_MIN_SHIFTREDUCE Minimum value for shift-reduce actions
** YY_MAX_SHIFTREDUCE Maximum value for shift-reduce actions
** YY_MIN_REDUCE Maximum value for reduce actions
** YY_ERROR_ACTION The yy_action[] code for syntax error
** YY_ACCEPT_ACTION The yy_action[] code for accept
** YY_NO_ACTION The yy_action[] code for no-op
*/
/************* Begin control #defines *****************************************/
%%
/************* End control #defines *******************************************/
/* Define the yytestcase() macro to be a no-op if is not already defined
** otherwise.
**
** Applications can choose to define yytestcase() in the %include section
** to a macro that can assist in verifying code coverage. For production
** code the yytestcase() macro should be turned off. But it is useful
** for testing.
*/
if (!this.yytestcase) {
this.yytestcase = function () {};
}
/* Next are the tables used to determine what action to take based on the
** current state and lookahead token. These tables are used to implement
** functions that take a state number and lookahead value and return an
** action integer.
**
** Suppose the action integer is N. Then the action is determined as
** follows
**
** 0 <= N <= YY_MAX_SHIFT Shift N. That is, push the lookahead
** token onto the stack and goto state N.
**
** N between YY_MIN_SHIFTREDUCE Shift to an arbitrary state then
** and YY_MAX_SHIFTREDUCE reduce by rule N-YY_MIN_SHIFTREDUCE.
**
** N between YY_MIN_REDUCE Reduce by rule N-YY_MIN_REDUCE
** and YY_MAX_REDUCE
**
** N == YY_ERROR_ACTION A syntax error has occurred.
**
** N == YY_ACCEPT_ACTION The parser accepts its input.
**
** N == YY_NO_ACTION No such action. Denotes unused
** slots in the yy_action[] table.
**
** The action table is constructed as a single large table named yy_action[].
** Given state S and lookahead X, the action is computed as either:
**
** (A) N = yy_action[ yy_shift_ofst[S] + X ]
** (B) N = yy_default[S]
**
** The (A) formula is preferred. The B formula is used instead if:
** (1) The yy_shift_ofst[S]+X value is out of range, or
** (2) yy_lookahead[yy_shift_ofst[S]+X] is not equal to X, or
** (3) yy_shift_ofst[S] equal YY_SHIFT_USE_DFLT.
** (Implementation note: YY_SHIFT_USE_DFLT is chosen so that
** YY_SHIFT_USE_DFLT+X will be out of range for all possible lookaheads X.
** Hence only tests (1) and (2) need to be evaluated.)
**
** The formulas above are for computing the action when the lookahead is
** a terminal symbol. If the lookahead is a non-terminal (as occurs after
** a reduce action) then the yy_reduce_ofst[] array is used in place of
** the yy_shift_ofst[] array and YY_REDUCE_USE_DFLT is used in place of
** YY_SHIFT_USE_DFLT.
**
** The following are the tables generated in this section:
**
** yy_action[] A single table containing all actions.
** yy_lookahead[] A table containing the lookahead for each entry in
** yy_action. Used to detect hash collisions.
** yy_shift_ofst[] For each state, the offset into yy_action for
** shifting terminals.
** yy_reduce_ofst[] For each state, the offset into yy_action for
** shifting non-terminals after a reduce.
** yy_default[] Default action for each state.
**
*********** Begin parsing tables **********************************************/
%%
/********** End of lemon-generated parsing tables *****************************/
/* The next table maps tokens (terminal symbols) into fallback tokens.
** If a construct like the following:
**
** %fallback ID X Y Z.
**
** appears in the grammar, then ID becomes a fallback token for X, Y,
** and Z. Whenever one of the tokens X, Y, or Z is input to the parser
** but it does not parse, the type of the token is changed to ID and
** the parse is retried before an error is thrown.
**
** This feature can be used, for example, to cause some keywords in a language
** to revert to identifiers if they keyword does not apply in the context where
** it appears.
*/
this.yyFallback = [
%%
];
/* The following structure represents a single element of the
** parser's stack. Information stored includes:
**
** + The state number for the parser at this level of the stack.
**
** + The value of the token stored at this level of the stack.
** (In other words, the "major" token.)
**
** + The semantic value stored at this level of the stack. This is
** the information used by the action routines in the grammar.
** It is sometimes called the "minor" token.
**
** After the "shift" half of a SHIFTREDUCE action, the stateno field
** actually contains the reduce action for the second half of the
** SHIFTREDUCE.
*/
//{
// stateno, /* The state-number, or reduce action in SHIFTREDUCE */
// major, /* The major token value. This is the code
// ** number for the token at this stack level */
// minor, /* The user-supplied minor token value. This
// ** is the value of the token */
//}
/* The state of the parser is completely contained in an instance of
** the following structure */
this.yyhwm = 0; /* High-water mark of the stack */
this.yyerrcnt = -1; /* Shifts left before out of the error */
this.yystack = null; /* The parser's stack */
this.yyidx = -1; /* Stack index of current element in the stack */
this.yyTraceCallback = null;
this.yyTracePrompt = "";
/*
** Turn parser tracing on by giving a stream to which to write the trace
** and a prompt to preface each trace message. Tracing is turned off
** by making either argument NULL
**
** Inputs:
** <ul>
** <li> A callback to which trace output should be written.
** If NULL, then tracing is turned off.
** <li> A prefix string written at the beginning of every
** line of trace output. Default is "".
** </ul>
**
** Outputs:
** None.
*/
this.setTraceCallback = function (callback, prompt) {
this.yyTraceCallback = callback;
this.yyTracePrompt = prompt || "";
}
this.trace = function (message) {
this.yyTraceCallback(this.yyTracePrompt + message + "\n");
}
/* For tracing shifts, the names of all terminals and nonterminals
** are required. The following table supplies these names */
this.yyTokenName = [
%%
];
/* For tracing reduce actions, the names of all rules are required.
*/
this.yyRuleName = [
%%
];
/*
** Try to increase the size of the parser stack. Return the number
** of errors. Return 0 on success.
*/
this.yyGrowStack = function () {
// fix me: yystksz*2 + 100
this.yystack.push({
stateno: undefined,
major: undefined,
minor: undefined
});
}
/* Initialize a new parser that has already been allocated.
*/
this.init = function () {
this.yyhwm = 0;
this.yyerrcnt = -1;
this.yyidx = 0;
if (this.YYSTACKDEPTH <= 0) {
this.yystack = [];
this.yyGrowStack();
} else {
this.yystack = new Array(this.YYSTACKDEPTH);
for (var i = 0; i < this.YYSTACKDEPTH; i++) {
this.yystack[i] = {
stateno: undefined,
major: undefined,
minor: undefined
};
}
}
var yytos = this.yystack[0];
yytos.stateno = 0;
yytos.major = 0;
}
/* The following function deletes the "minor type" or semantic value
** associated with a symbol. The symbol can be either a terminal
** or nonterminal. "yymajor" is the symbol code, and "yypminor" is
** a pointer to the value to be deleted. The code used to do the
** deletions is derived from the %destructor and/or %token_destructor
** directives of the input grammar.
*/
this.yy_destructor = function (
yymajor, /* Type code for object to destroy */
yyminor /* The object to be destroyed */
) {
switch (yymajor) {
/* Here is inserted the actions which take place when a
** terminal or non-terminal is destroyed. This can happen
** when the symbol is popped from the stack during a
** reduce or during error processing or when a parser is
** being destroyed before it is finished parsing.
**
** Note: during a reduce, the only symbols destroyed are those
** which appear on the RHS of the rule, but which are *not* used
** inside the C code.
*/
/********* Begin destructor definitions ***************************************/
%%
/********* End destructor definitions *****************************************/
default: break; /* If no destructor action specified: do nothing */
}
}
/*
** Pop the parser's stack once.
**
** If there is a destructor routine associated with the token which
** is popped from the stack, then call it.
*/
this.yy_pop_parser_stack = function () {
// assert( pParser->yytos!=0 );
// assert( pParser->yytos > pParser->yystack );
var yytos = this.yystack[this.yyidx];
if (this.yyTraceCallback) {
this.trace("Popping " + this.yyTokenName[yytos.major]);
}
this.yy_destructor(yytos.major, yytos.minor);
this.yyidx--;
}
/*
** Clear all secondary memory allocations from the parser
*/
this.finalize = function () {
while (this.yyidx > 0) {
this.yy_pop_parser_stack();
}
this.yystack = null;
}
/*
** Return the peak depth of the stack for a parser.
*/
this.getStackPeak = function () {
return this.yyhwm;
}
/*
** Find the appropriate action for a parser given the terminal
** look-ahead token iLookAhead.
*/
this.yy_find_shift_action = function (
iLookAhead /* The look-ahead token */
) {
var yytos = this.yystack[this.yyidx];
var stateno = yytos.stateno;
if (stateno >= this.YY_MIN_REDUCE) {
return stateno;
}
// assert( stateno <= YY_SHIFT_COUNT );
do {
var i = this.yy_shift_ofst[stateno];
// assert( iLookAhead!=YYNOCODE );
i += iLookAhead;
if (i < 0 || i >= this.yy_action.length || this.yy_lookahead[i] != iLookAhead) {
if (this.YYFALLBACK) {
var iFallback; /* Fallback token */
if ((iLookAhead < this.yyFallback.length)
&& (iFallback = this.yyFallback[iLookAhead]) != 0
) {
if (this.yyTraceCallback) {
this.trace("FALLBACK " + this.yyTokenName[iLookAhead] + " => " + this.yyTokenName[iFallback]);
}
}
// assert( yyFallback[iFallback]==0 ); /* Fallback loop must terminate */
iLookAhead = iFallback;
continue;
}
if (this.YYWILDCARD) {
var j = i - iLookAhead + this.YYWILDCARD;
var cond1 = (this.YY_SHIFT_MIN + this.YYWILDCARD) < 0 ? j >= 0 : true;
var cond2 = (this.YY_SHIFT_MAX + this.YYWILDCARD) >= this.yy_action.length ? j < this.yy_action.length : true;
if (cond1 && cond2 && this.yy_lookahead[j] == this.YYWILDCARD && iLookAhead > 0) {
if (this.yyTraceCallback) {
this.trace("WILDCARD " + this.yyTokenName[iLookAhead] + " => " + this.yyTokenName[this.YYWILDCARD]);
}
return this.yy_action[j];
}
}
return this.yy_default[stateno];
} else {
return this.yy_action[i];
}
} while (true);
}
/*
** Find the appropriate action for a parser given the non-terminal
** look-ahead token iLookAhead.
*/
this.yy_find_reduce_action = function (
stateno, /* Current state number */
iLookAhead /* The look-ahead token */
) {
if (this.YYERRORSYMBOL) {
if (stateno > this.YY_REDUCE_COUNT) {
return this.yy_default[stateno];
}
} else {
// assert( stateno<=YY_REDUCE_COUNT );
}
var i = this.yy_reduce_ofst[stateno];
// assert( i!=YY_REDUCE_USE_DFLT );
// assert( iLookAhead!=YYNOCODE );
i += iLookAhead;
if (this.YYERRORSYMBOL) {
if (i < 0 || i >= this.yy_action.length || this.yy_lookahead[i] != iLookAhead) {
return this.yy_default[stateno];
}
} else {
// assert( i>=0 && i<YY_ACTTAB_COUNT );
// assert( yy_lookahead[i]==iLookAhead );
}
return this.yy_action[i];
}
/*
** The following routine is called if the stack overflows.
*/
this.yyStackOverflow = function () {
if (this.yyTraceCallback) {
this.trace("Stack Overflow!");
}
while (this.yyidx > 0) {
this.yy_pop_parser_stack();
}
/* Here code is inserted which will execute if the parser
** stack every overflows */
/******** Begin %stack_overflow code ******************************************/
%%
/******** End %stack_overflow code ********************************************/
}
/*
** Print tracing information for a SHIFT action
*/
this.yyTraceShift = function (yyNewState) {
if (this.yyTraceCallback) {
var yytos = this.yystack[this.yyidx];
if (yyNewState < this.YYNSTATE) {
this.trace("Shift '" + this.yyTokenName[yytos.major] + "', go to state " + yyNewState);
} else {
this.trace("Shift '" + this.yyTokenName[yytos.major] + "'");
}
}
}
/*
** Perform a shift action.
*/
this.yy_shift = function (
yyNewState, /* The new state to shift in */
yyMajor, /* The major token to shift in */
yyMinor /* The minor token to shift in */
) {
this.yyidx++;
if (this.yyidx > this.yyhwm) {
this.yyhwm++;
// assert( yypParser->yyhwm == (int)(yypParser->yytos - yypParser->yystack) );
}
if (this.YYSTACKDEPTH > 0) {
if (this.yyidx >= this.YYSTACKDEPTH) {
this.yyidx--;
this.yyStackOverflow();
return;
}
} else {
if (this.yyidx >= this.yystack.length) {
this.yyGrowStack();
}
}
if (yyNewState > this.YY_MAX_SHIFT) {
yyNewState += this.YY_MIN_REDUCE - this.YY_MIN_SHIFTREDUCE;
}
var yytos = this.yystack[this.yyidx];
yytos.stateno = yyNewState;
yytos.major = yyMajor;
yytos.minor = yyMinor;
this.yyTraceShift(yyNewState);
}
/* The following table contains information about every rule that
** is used during the reduce.
*/
//{
// lhs, /* Symbol on the left-hand side of the rule */
// nrhs, /* Number of right-hand side symbols in the rule */
//}
this.yyRuleInfo = [
%%
];
/*
** Perform a reduce action and the shift that must immediately
** follow the reduce.
*/
this.yy_reduce = function (
yyruleno /* Number of the rule by which to reduce */
){
var yymsp = this.yystack[this.yyidx]; /* The top of the parser's stack */
if (yyruleno < this.yyRuleName.length) {
var yysize = this.yyRuleInfo[yyruleno].nrhs;
var ruleName = this.yyRuleName[yyruleno];
var newStateNo = this.yystack[this.yyidx - yysize].stateno;
if (this.yyTraceCallback) {
this.trace("Reduce [" + ruleName + "], go to state " + newStateNo + ".");
}
}
/* Check that the stack is large enough to grow by a single entry
** if the RHS of the rule is empty. This ensures that there is room
** enough on the stack to push the LHS value */
if (this.yyRuleInfo[yyruleno].nrhs == 0) {
if (this.yyidx > this.yyhwm) {
this.yyhwm++;
// assert( yypParser->yyhwm == (int)(yypParser->yytos - yypParser->yystack));
}
if (this.YYSTACKDEPTH > 0) {
if (this.yyidx >= this.YYSTACKDEPTH - 1) {
this.yyStackOverflow();
return;
}
} else {
if (this.yyidx >= this.yystack.length - 1) {
this.yyGrowStack();
yymsp = this.yystack[this.yyidx];
}
}
}
var yylhsminor;
switch (yyruleno) {
/* Beginning here are the reduction cases. A typical example
** follows:
** case 0:
** #line <lineno> <grammarfile>
** { ... } // User supplied code
** #line <lineno> <thisfile>
** break;
*/
/********** Begin reduce actions **********************************************/
%%
/********** End reduce actions ************************************************/
};
// assert( yyruleno<sizeof(yyRuleInfo)/sizeof(yyRuleInfo[0]) );
var yygoto = this.yyRuleInfo[yyruleno].lhs; /* The next state */
var yysize = this.yyRuleInfo[yyruleno].nrhs; /* Amount to pop the stack */
var yyact = this.yy_find_reduce_action( /* The next action */
this.yystack[this.yyidx - yysize].stateno,
yygoto
);
if (yyact <= this.YY_MAX_SHIFTREDUCE) {
if (yyact > this.YY_MAX_SHIFT) {
yyact += this.YY_MIN_REDUCE - this.YY_MIN_SHIFTREDUCE;
}
this.yyidx -= yysize - 1;
yymsp = this.yystack[this.yyidx];
yymsp.stateno = yyact;
yymsp.major = yygoto;
this.yyTraceShift(yyact);
} else {
// assert( yyact == YY_ACCEPT_ACTION );
this.yyidx -= yysize;
this.yy_accept();
}
}
/*
** The following code executes when the parse fails
*/
this.yy_parse_failed = function () {
if (this.yyTraceCallback) {
this.trace("Fail!");
}
while (this.yyidx > 0) {
this.yy_pop_parser_stack();
}
/* Here code is inserted which will be executed whenever the
** parser fails */
/************ Begin %parse_failure code ***************************************/
%%
/************ End %parse_failure code *****************************************/
}
/*
** The following code executes when a syntax error first occurs.
*/
this.yy_syntax_error = function (
yymajor, /* The major type of the error token */
yyminor /* The minor type of the error token */
) {
var TOKEN = yyminor;
/************ Begin %syntax_error code ****************************************/
%%
/************ End %syntax_error code ******************************************/
}
/*
** The following is executed when the parser accepts
*/
this.yy_accept = function () {
if (this.yyTraceCallback) {
this.trace("Accept!");
}
if (!this.YYNOERRORRECOVERY) {
this.yyerrcnt = -1;
}
// assert( yypParser->yytos==yypParser->yystack );
/* Here code is inserted which will be executed whenever the
** parser accepts */
/*********** Begin %parse_accept code *****************************************/
%%
/*********** End %parse_accept code *******************************************/
}
/* The main parser program.
** The first argument is a pointer to a structure obtained from
** "ParseAlloc" which describes the current state of the parser.
** The second argument is the major token number. The third is
** the minor token. The fourth optional argument is whatever the
** user wants (and specified in the grammar) and is available for
** use by the action routines.
**
** Inputs:
** <ul>
** <li> A pointer to the parser (an opaque structure.)
** <li> The major token number.
** <li> The minor token number.
** <li> An option argument of a grammar-specified type.
** </ul>
**
** Outputs:
** None.
*/
this.parse = function (
yymajor, /* The major token code number */
yyminor /* The value for the token */
) {
var yyact; /* The parser action. */
var yyendofinput; /* True if we are at the end of input */
var yyerrorhit = 0; /* True if yymajor has invoked an error */
//assert( yypParser->yytos!=0 );
if (yymajor === undefined || yymajor === null) {
yymajor = 0;
}
yyendofinput = yymajor == 0;
if (this.yyTraceCallback) {
this.trace("Input '" + this.yyTokenName[yymajor] + "'");
}
do {
yyact = this.yy_find_shift_action(yymajor);
if (yyact <= this.YY_MAX_SHIFTREDUCE) { // check me?
this.yy_shift(yyact, yymajor, yyminor);
if (!this.YYNOERRORRECOVERY) {
this.yyerrcnt--;
}
yymajor = this.YYNOCODE;
} else if (yyact <= this.YY_MAX_REDUCE) { // check me?
this.yy_reduce(yyact - this.YY_MIN_REDUCE); // check me?
} else {
// assert( yyact == YY_ERROR_ACTION );
if (this.yyTraceCallback) {
this.trace("Syntax Error!");
}
if (this.YYERRORSYMBOL) {
/* A syntax error has occurred.
** The response to an error depends upon whether or not the
** grammar defines an error token "ERROR".
**
** This is what we do if the grammar does define ERROR:
**
** * Call the %syntax_error function.
**
** * Begin popping the stack until we enter a state where
** it is legal to shift the error symbol, then shift
** the error symbol.
**
** * Set the error count to three.
**
** * Begin accepting and shifting new tokens. No new error
** processing will occur until three tokens have been
** shifted successfully.
**
*/
if (this.yyerrcnt < 0) {
this.yy_syntax_error(yymajor, yyminor);
}
var yymx = this.yystack[this.yyidx].major;
if (yymx == this.YYERRORSYMBOL || yyerrorhit) {
if (this.yyTraceCallback) {
this.trace("Discard input token " + this.yyTokenName[yymajor]);
}
this.yy_destructor(yymajor, yyminor);
yymajor = this.YYNOCODE;
} else {
while (this.yyidx >= 0
&& yymx != this.YYERRORSYMBOL
&& (yyact = this.yy_find_reduce_action(
this.yystack[this.yyidx].stateno,
this.YYERRORSYMBOL)) >= this.YY_MIN_REDUCE // check me?
) {
this.yy_pop_parser_stack();
}
if (this.yyidx < 0 || yymajor == 0) {
this.yy_destructor(yymajor, yyminor);
this.yy_parse_failed();
if (!this.YYNOERRORRECOVERY) {
this.yyerrcnt = -1;
}
yymajor = this.YYNOCODE;
} else if (yymx != this.YYERRORSYMBOL) {
this.yy_shift(yyact, this.YYERRORSYMBOL, yyminor); // check me?
}
}
this.yyerrcnt = 3;
yyerrorhit = 1;
} else if (this.YYNOERRORRECOVERY) {
/* If the YYNOERRORRECOVERY macro is defined, then do not attempt to
** do any kind of error recovery. Instead, simply invoke the syntax
** error routine and continue going as if nothing had happened.
**
** Applications can set this macro (for example inside %include) if
** they intend to abandon the parse upon the first syntax error seen.
*/
this.yy_syntax_error(yymajor, yyminor);
this.yy_destructor(yymajor, yyminor);
yymajor = this.YYNOCODE;
} else { /* YYERRORSYMBOL is not defined */
/* This is what we do if the grammar does not define ERROR:
**
** * Report an error message, and throw away the input token.
**
** * If the input token is $, then fail the parse.
**
** As before, subsequent error messages are suppressed until
** three input tokens have been successfully shifted.
*/
if (this.yyerrcnt <= 0) {
this.yy_syntax_error(yymajor, yyminor);
}
this.yyerrcnt = 3;
this.yy_destructor(yymajor, yyminor);
if (yyendofinput) {
this.yy_parse_failed();
if (!this.YYNOERRORRECOVERY) {
this.yyerrcnt = -1;
}
}
yymajor = this.YYNOCODE;
}
}
} while (yymajor != this.YYNOCODE && this.yyidx > 0);
if (this.yyTraceCallback) {
var remainingTokens = [];
for (var i = 1; i <= this.yyidx; i++) {
remainingTokens.push(this.yyTokenName[this.yystack[i].major]);
}
this.trace("Return. Stack=[" + remainingTokens.join(" ") + "]");
}
}
this.init();
} // function Parse()