Generator::computeFollow() - Code Metrics - stenin-nikita/PHP-Yacc - Measure and Improve Code Quality continuously with Scrutinizer

Generator::computeFollow() C
last analyzed 2018-07-30 10:30 UTC

↳ Parent: Generator
Complexity

Conditions	16
Paths	60
Size

Total Lines
Duplication

Lines	6
Ratio	19.35 %
Importance

Changes
Metric	Value
dl	6
loc	31
rs	5.5666
c	0
b	0
f	0
cc	16
nc	60
nop	1
How to fix Complexity

<?php
/**
 * This file is part of PHP-Yacc package.
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */
declare(strict_types=1);

namespace PhpYacc\Lalr;

use PhpYacc\Exception\LogicException;
use PhpYacc\Grammar\Context;
use PhpYacc\Grammar\State;
use PhpYacc\Grammar\Symbol;
use PhpYacc\Lalr\Conflict\ReduceReduce;
use PhpYacc\Lalr\Conflict\ShiftReduce;
use PhpYacc\Support\Utils;
use PhpYacc\Yacc\Production;

/**
 * Class Generator.
 */
class Generator
{
    const NON_ASSOC = -32768;

    /**
     * @var Context
     */
    protected $context;

    protected $nullable;
    protected $blank;

    /**
     * @var array|State[][]
     */
    protected $statesThrough = [];

    /**
     * @var array
     */
    protected $visited = [];

    /**
     * @var BitSet[]
     */
    protected $first;

    /**
     * @var BitSet[]
     */
    protected $follow;

    /**
     * @var State[]
     */
    protected $states;

    /**
     * @var int
     */
    protected $countLooks;

    /**
     * @var int
     */
    protected $countStates;

    /**
     * @var int
     */
    protected $countActions;

    /**
     * @var int
     */
    protected $countActions2;

    /**
     * @var int
     */
    protected $countNonLeafStates;
    protected $nsrerr;
    protected $nrrerr;

    /**
     * @param Context $context
     *
     * @throws LogicException
     *
     * @return void
     */
    public function compute(Context $context)
    {
        $this->context = $context;
        // Ensure nil symbol is part of nSymbols
        $this->context->nilSymbol();
        $this->context->finish();
        $countSymbols = $this->context->countSymbols;
        $this->nullable = \array_fill(0, $countSymbols, false);

        $this->blank = new ArrayBitSet($countSymbols);
        $this->states = [];
        $this->countLooks = $this->countStates = $this->countActions = $this->countActions2 = 0;
        $this->countNonLeafStates = 0;
        $this->nsrerr = $this->nrrerr = 0;

        $this->statesThrough = [];
        $this->first = [];
        $this->follow = [];

        foreach ($this->context->symbols as $s) {
            $this->first[$s->code] = clone $this->blank;
            $this->follow[$s->code] = clone $this->blank;
            $this->statesThrough[$s->code] = [];
        }

        $this->computeEmpty();
        $this->firstNullablePrecomp();
        $this->computeKernels();
        $this->computeLookaheads();
        $this->fillReduce();
        $this->printDiagnostics();
        $this->printStatistics();

        $this->context->states = $this->states;
        $this->context->countNonLeafStates = $this->countNonLeafStates;
    }

    /**
     * @return void
     */
    protected function computeKernels()
    {
        $tmpList = new Lr1(null, clone $this->blank, new Item($this->context->gram(0), 1));
        $this->findOrCreateState($this->context->nilsymbol, $tmpList);

        // foreach by ref so that new additions to $this->states are also picked up
        foreach ($this->states as &$p) {
            // Collect direct GOTO's (come from kernel items)

            /** @var Lr1|null $tmpList */
            /** @var Lr1|null $tmpTail */
            $tmpList = $tmpTail = null;

            /** @var Lr1 $x */
            for ($x = $p->items; $x !== null; $x = $x->next) {
                if (!$x->isTailItem()) {
                    $wp = new Lr1(null, clone $this->blank, $x->item->slice(1));
                    if ($tmpTail !== null) {
                        $tmpTail->next = $wp;
                    } else {
                        $tmpList = $wp;
                    }
                    $tmpTail = $wp;
                }
            }

            // Collect indirect GOTO's (come from nonkernel items)
            $this->clearVisited();
            for ($tp = $tmpList; $tp != null; $tp = $tp->next) {
                /** @var Symbol $g */
                $g = $tp->item[-1];
                if ($g !== null && !$g->isTerminal && !$this->visited[$g->code]) {
                    $this->visited[$g->code] = true;
                    /** @var Production $gram */
                    for ($gram = $g->value; $gram != null; $gram = $gram->link) {
                        if (isset($gram->body[1])) {
                            $wp = new Lr1($g, clone $this->blank, new Item($gram, 2));
                            $tmpTail->next = $wp;
                            $tmpTail = $wp;
                        }
                    }
                }
            }

            $tmpList = $this->sortList($tmpList, function (Lr1 $x, Lr1 $y) {
                $gx = $x->item[-1]->code;
                $gy = $y->item[-1]->code;
                if ($gx !== $gy) {
                    return $gx - $gy;
                }
                $px = $x->item->getProduction();
                $py = $y->item->getProduction();
                if ($px !== $py) {
                    return $px->num - $py->num;
                }

                return $x->item->getPos() - $y->item->getPos();
            });

            // Compute next states
            $nextStates = [];
            for ($tp = $tmpList; $tp !== null;) {
                $sp = null;

                $g = $tp->item[-1];
                $sublist = $tp;
                while ($tp != null && $tp->item[-1] === $g) {
                    $sp = $tp;
                    $tp = $tp->next;
                }
                $sp->next = null;

                $nextStates[] = $this->findOrCreateState($g, $sublist);
            }

            $p->shifts = $nextStates;
            $this->countActions += \count($nextStates);
        }
    }

    /**
     * @return void
     */
    protected function computeLookaheads()
    {
        $this->states[0]->items->look->setBit(0);
        do {
            $changed = false;
            foreach ($this->states as $p) {
                $this->computeFollow($p);
                for ($x = $p->items; $x !== null; $x = $x->next) {
                    $g = $x->item[0] ?? null;
                    if (null !== $g) {
                        $s = $x->item->slice(1);
                        $t = null;
                        foreach ($p->shifts as $t) {
                            if ($t->through === $g) {
                                break;
                            }
                        }
                        \assert($t->through === $g);
                        for ($y = $t->items; $y !== null; $y = $y->next) {
                            if ($y->item == $s) {
                                break;
                            }
                        }
                        \assert($y->item == $s);
                        $changed |= $y->look->or($x->look);
                    }
                }

                foreach ($p->shifts as $t) {
                    for ($x = $t->items; $x !== null; $x = $x->next) {
                        if ($x->left !== null) {

                            $changed |= $x->look->or($this->follow[$x->left->code]);
                        }
                    }
                }

                for ($x = $p->items; $x !== null; $x = $x->next) {

                    if ($x->isTailItem() && $x->isHeadItem()) {
                        $x->look->or($this->follow[$x->item[-1]->code]);
function acceptsInteger($int) { }

$x = '123'; // string "123"

// Instead of
acceptsInteger($x);

// we recommend to use
acceptsInteger((integer) $x);
                    }
                }
            }
        } while ($changed);

        if ($this->context->debug) {
            foreach ($this->states as $p) {
                $this->context->debug("state unknown:\n");
                for ($x = $p->items; $x != null; $x = $x->next) {
                    $this->context->debug("\t".\trim((string) $x->item)."\n");
                    $this->context->debug("\t\t[ ");
                    $this->context->debug(Utils::dumpSet($this->context, $x->look));
                    $this->context->debug("]\n");
                }
            }
        }
    }

    /**
     * @throws LogicException
     *
     * @return void
     */
    protected function fillReduce()
    {
        $this->clearVisited();

        foreach ($this->states as $p) {
            /** @var Reduce[] $tmpr */
            $tmpr = [];

            $tdefact = 0;
            foreach ($p->shifts as $t) {
                if ($t->through === $this->context->errorToken) {
                    // shifting error
                    $tdefact = -1;
                }
            }

            // Pick up reduce entries
            for ($x = $p->items; $x !== null; $x = $x->next) {
                if (!$x->isTailItem()) {
                    continue;
                }

                $alook = clone $x->look;
                $gram = $x->item->getProduction();

                // find shift/reduce conflict
                foreach ($p->shifts as $m => $t) {
                    $e = $t->through;
                    if (!$e->isTerminal) {
                        break;
                    }
                    if ($alook->testBit($e->code)) {
                        $rel = $this->comparePrecedence($gram, $e);
                        if ($rel === self::NON_ASSOC) {
                            $alook->clearBit($e->code);
                            unset($p->shifts[$m]);
                            $tmpr[] = new Reduce($e, -1);
                        } elseif ($rel < 0) {
                            // reduce
                            unset($p->shifts[$m]);
                        } elseif ($rel > 0) {
                            // shift
                            $alook->clearBit($e->code);
                        } elseif ($rel == 0) {
                            // conflict
                            $alook->clearBit($e->code);
                            $this->nsrerr++;
                            $p->conflict = new Conflict\ShiftReduce($t, $gram->num, $e, $p->conflict);
                        }
                    }
                }

                foreach ($tmpr as $reduce) {
                    if ($alook->testBit($reduce->symbol->code)) {
                        // reduce/reduce conflict
                        $this->nrrerr++;
                        $p->conflict = new Conflict\ReduceReduce(
                            $reduce->number,
                            $gram->num,
                            $reduce->symbol,
                            $p->conflict
                        );

                        if ($gram->num < $reduce->number) {
                            $reduce->number = $gram->num;
                        }
                        $alook->clearBit($reduce->symbol->code);
                    }
                }

                foreach ($alook as $e) {
                    $sym = $this->context->symbols[$e];
                    $tmpr[] = new Reduce($sym, $gram->num);
                }
            }

            // Decide default action
            if (!$tdefact) {
                $tdefact = -1;

                Utils::stableSort($tmpr, function (Reduce $x, Reduce $y) {

                    if ($x->number != $y->number) {
                        return $y->number - $x->number;
                    }

                    return $x->symbol->code - $y->symbol->code;
                });

                $maxn = 0;
                $nr = \count($tmpr);
                for ($j = 0; $j < $nr;) {
                    for ($k = $j; $j < $nr; $j++) {
                        if ($tmpr[$j]->number != $tmpr[$k]->number) {
                            break;
                        }
                    }
                    if ($j - $k > $maxn && $tmpr[$k]->number > 0) {
                        $maxn = $j - $k;
                        $tdefact = $tmpr[$k]->number;
                    }
                }
            }

            // Squeeze tmpr
            $tmpr = \array_filter($tmpr, function (Reduce $reduce) use ($tdefact) {
                return $reduce->number !== $tdefact;
            });

            Utils::stableSort($tmpr, function (Reduce $x, Reduce $y) {

                if ($x->symbol !== $y->symbol) {
                    return $x->symbol->code - $y->symbol->code;
                }

                return $x->number - $y->number;
            });
            $tmpr[] = new Reduce($this->context->nilsymbol, $tdefact);

            // Squeeze shift actions (we deleted some keys)
            $p->shifts = \array_values($p->shifts);

            foreach ($tmpr as $reduce) {
                if ($reduce->number >= 0) {
                    $this->visited[$reduce->number] = true;
                }
            }

            // Register tmpr
            $p->reduce = $tmpr;
            $this->countActions2 += \count($tmpr);
        }

        $k = 0;
        foreach ($this->context->grams as $gram) {
            if (!$this->visited[$gram->num]) {
                $k++;
                $this->context->debug("Never reduced: \n"); // TODO
            }
        }

        if ($k) {
            $this->context->debug($k." rule(s) never reduced\n");
        }

        // Sort states in decreasing order of entries
        // do not move initial state
        $initState = \array_shift($this->states);

        Utils::stableSort($this->states, function (State $p, State $q) {
            $numReduces = count($p->reduce) - 1; // -1 for default action
            $pt = $numReduces;
            $pn = count($p->shifts) + $numReduces;
            foreach ($p->shifts as $x) {
                if ($x->through->isTerminal) {
                    $pt++;
                }
            }

            $numReduces = \count($q->reduce) - 1; // -1 for default action
            $qt = $numReduces;
            $qn = \count($q->shifts) + $numReduces;
            foreach ($q->shifts as $x) {
                if ($x->through->isTerminal) {
                    $qt++;
                }
            }

            if ($pt !== $qt) {
                return $qt - $pt;
            }

            return $qn - $pn;
        });

        array_unshift($this->states, $initState);

        foreach ($this->states as $i => $p) {
            $p->number = $i;
            if (!empty($p->shifts) || !$p->reduce[0]->symbol->isNilSymbol()) {
                $this->countNonLeafStates = $i + 1;
class Id
{
    public $id;

    public function __construct($id)
    {
        $this->id = $id;
    }

}

class Account
{
    /** @var  Id $id */
    public $id;
}

$account_id = false;

if (starsAreRight()) {
    $account_id = new Id(42);
}

$account = new Account();
if ($account instanceof Id)
{
    $account->id = $account_id;
}
            }
        }

        foreach ($this->states as $state) {
            $this->printState($state);
        }
    }

    /**
     * @param Production $gram
     * @param Symbol     $x
     *
     * @throws LogicException
     *
     * @return int|mixed
     */
    protected function comparePrecedence(Production $gram, Symbol $x)
    {
        if ($gram->associativity === Symbol::UNDEF
            || ($x->associativity & Symbol::MASK) === Symbol::UNDEF
        ) {
            return 0;
        }

        $v = $x->precedence - $gram->precedence;
        if ($v !== 0) {
            return $v;
        }

        switch ($gram->associativity) {
            case Symbol::LEFT:
switch ($expr) {
    case "A": { //wrong
        doSomething();
        break;
    }
    case "B"; //wrong
        doSomething();
        break;
    case "C": //right
        doSomething();
        break;
}
                return -1;
            case Symbol::RIGHT:
switch ($expr) {
    case "A": { //wrong
        doSomething();
        break;
    }
    case "B"; //wrong
        doSomething();
        break;
    case "C": //right
        doSomething();
        break;
}
                return 1;
            case Symbol::NON:
                return self::NON_ASSOC;
        }

        throw new LogicException('Gram has associativity other than LEFT/RIGHT/NON. This should never happen');
    }

    /**
     * @param State $st
     */
    protected function computeFollow(State $st)
    {
        foreach ($st->shifts as $t) {
            if (!$t->through->isTerminal) {
                $this->follow[$t->through->code] = clone $this->blank;
                for ($x = $t->items; $x !== null && !$x->isHeadItem(); $x = $x->next) {

                    $this->computeFirst($this->follow[$t->through->code], $x->item);
                }
            }
        }
        for ($x = $st->items; $x !== null; $x = $x->next) {
            /** @var Symbol $g */
            $g = $x->item[0] ?? null;
            if ($g !== null && !$g->isTerminal && $this->isSeqNullable($x->item->slice(1))) {
                $this->follow[$g->code]->or($x->look);
function acceptsInteger($int) { }

$x = '123'; // string "123"

// Instead of
acceptsInteger($x);

// we recommend to use
acceptsInteger((integer) $x);
            }
        }
        do {
            $changed = false;
            foreach ($st->shifts as $t) {
                if (!$t->through->isTerminal) {
                    $p = $this->follow[$t->through->code];
                    for ($x = $t->items; $x !== null && !$x->isHeadItem(); $x = $x->next) {
                        if ($this->isSeqNullable($x->item) && $x->left != null) {

                            $changed |= $p->or($this->follow[$x->left->code]);
                        }
                    }
                }
            }
        } while ($changed);
    }

    /**
     * @param BitSet $p
     * @param Item   $item
     */
    protected function computeFirst(BitSet $p, Item $item)
    {
        /** @var Symbol $g */
        foreach ($item as $g) {
            if ($g->isTerminal) {
                $p->setBit($g->code);

                return;
            }
            $p->or($this->first[$g->code]);
function acceptsInteger($int) { }

$x = '123'; // string "123"

// Instead of
acceptsInteger($x);

// we recommend to use
acceptsInteger((integer) $x);
            if (!$this->nullable[$g->code]) {
                return;
            }
        }
    }

    /**
     * @param Item $item
     *
     * @return bool
     */
    protected function isSeqNullable(Item $item)
    {
        /** @var Symbol $g */
        foreach ($item as $g) {
            if ($g->isTerminal || !$this->nullable[$g->code]) {
                return false;
            }
        }

        return true;
    }

    /**
     * @param Symbol $through
     * @param Lr1    $sublist
     *
     * @return State
     */
    protected function findOrCreateState(Symbol $through, Lr1 $sublist)
    {
        foreach ($this->statesThrough[$through->code] as $state) {
            if (Utils::isSameSet($state->items, $sublist)) {
                return $state;
            }
        }

        $state = new State($through, $this->makeState($sublist));
        $this->states[] = $state;
        $this->statesThrough[$through->code][] = $state;
        $this->countStates++;

        return $state;
    }

    /**
     * @return void
     */
    protected function computeEmpty()
    {
        do {
            $changed = false;
            foreach ($this->context->grams as $gram) {

                /** @var Symbol $left */
                $left = $gram->body[0];
                $right = $gram->body[1] ?? null;
                if (($right === null || ($right->associativity & Production::EMPTY)) && !($left->associativity & Production::EMPTY)) {
                    $left->setAssociativityFlag(Production::EMPTY);
                    $changed = true;
                }
            }
        } while ($changed);

        if ($this->context->debug) {
            $this->context->debug('EMPTY nonterminals: ');
            foreach ($this->context->nonterminals as $symbol) {
                if ($symbol->associativity & Production::EMPTY) {
                    $this->context->debug(' '.$symbol->name);
                }
            }
            $this->context->debug("\n");
        }
    }

    /**
     * @return void
     */
    protected function firstNullablePrecomp()
    {
        do {
            $changed = false;
            foreach ($this->context->grams as $gram) {
                $h = $gram->body[0];
                for ($s = 1, $l = \count($gram->body); $s < $l; $s++) {
                    $g = $gram->body[$s];
                    if ($g->isTerminal) {
                        if (!$this->first[$h->code]->testBit($g->code)) {
                            $changed = true;
                            $this->first[$h->code]->setBit($g->code);
                        }
                        continue 2;
                    }

                    $changed |= $this->first[$h->code]->or($this->first[$g->code]);
                    if (!$this->nullable[$g->code]) {
                        continue 2;
                    }
                }

                if (!$this->nullable[$h->code]) {
                    $this->nullable[$h->code] = true;
                    $changed = true;
                }
            }
        } while ($changed);

        if ($this->context->debug) {
            $this->context->debug("First:\n");
            foreach ($this->context->nonterminals as $symbol) {
                $this->context->debug("{$symbol->name}\t[ ");
                $this->context->debug(Utils::dumpSet($this->context, $this->first[$symbol->code]));
                if ($this->nullable[$symbol->code]) {
                    $this->context->debug('@ ');
                }
                $this->context->debug("]\n");
            }
        }
    }

    /**
     * @param Lr1 $items
     *
     * @return Lr1
     */
    protected function makeState(Lr1 $items): Lr1
    {
        $tail = null;
        for ($p = $items; $p !== null; $p = $p->next) {
            $p->look = null;
            if ($p->left !== null) {
                for ($q = $items; $q !== $p; $q = $q->next) {
                    if ($q->left === $p->left) {
                        $p->look = $q->look;
                        break;
                    }
                }
            }
            if ($p->look === null) {
                $p->look = clone $this->blank;
                $this->countLooks++;
            }
            $tail = $p;
        }
        $this->clearVisited();
        for ($p = $items; $p !== null; $p = $p->next) {
            /** @var Symbol $g */
            $g = $p->item[0] ?? null;
            if ($g !== null && !$g->isTerminal) {
                $tail = $this->findEmpty($tail, $g);
/** @return stdClass|null */
function mayReturnNull() { }

function doesNotAcceptNull(stdClass $x) { }

// With potential error.
function withoutCheck() {
    $x = mayReturnNull();
    doesNotAcceptNull($x); // Potential error here.
}

// Safe - Alternative 1
function withCheck1() {
    $x = mayReturnNull();
    if ( ! $x instanceof stdClass) {
        throw new \LogicException('$x must be defined.');
    }
    doesNotAcceptNull($x);
}

// Safe - Alternative 2
function withCheck2() {
    $x = mayReturnNull();
    if ($x instanceof stdClass) {
        doesNotAcceptNull($x);
    }
}
            }
        }

        return $items;
    }

    /**
     * @return void
     */
    protected function clearVisited()
    {
        $nSymbols = $this->context->countSymbols;
        $nGrams = $this->context->countGrams;
        $this->visited = array_fill(0, max($nSymbols, $nGrams), false);
    }

    /**
     * @param Lr1    $tail
     * @param Symbol $x
     *
     * @return Lr1
     */
    protected function findEmpty(Lr1 $tail, Symbol $x): Lr1
    {
        if (!$this->visited[$x->code] && ($x->associativity & Production::EMPTY)) {
            $this->visited[$x->code] = true;

            /** @var Production $gram */
            for ($gram = $x->value; $gram !== null; $gram = $gram->link) {
                if ($gram->isEmpty()) {
                    $p = new Lr1(null, clone $this->blank, new Item($gram, 1));
                    $tail->next = $p;
                    $tail = $p;
                    $this->countLooks++;
                } elseif (!$gram->body[1]->isTerminal) {
                    $tail = $this->findEmpty($tail, $gram->body[1]);
                }
            }
        }

        return $tail;
    }

    /**
     * @param Lr1|null $list
     * @param callable $cmp
     *
     * @return mixed|null|Lr1
     */
    protected function sortList(Lr1 $list = null, callable $cmp)
    {
        $array = [];
        for ($x = $list; $x !== null; $x = $x->next) {
            $array[] = $x;
        }

        Utils::stableSort($array, $cmp);

        $list = null;
        /** @var Lr1 $tail */
        $tail = null;
        foreach ($array as $x) {
            if ($list == null) {
                $list = $x;
            } else {
                $tail->next = $x;
            }
            $tail = $x;
            $x->next = null;
        }

        return $list;
    }

    /**
     * @param State $state
     */
    protected function printState(State $state)
    {
        $this->context->debug('state '.$state->number."\n");
        for ($conf = $state->conflict; $conf !== null; $conf = $conf->next()) {
            if ($conf instanceof ShiftReduce) {
                $this->context->debug(sprintf(
                    "%d: shift/reduce conflict (shift %d, reduce %d) on %s\n",
                    $state->number,
                    $conf->state()->number,
                    $conf->reduce(),
                    $conf->symbol()->name
                ));
            } elseif ($conf instanceof ReduceReduce) {
                $this->context->debug(sprintf(
                    "%d: reduce/reduce conflict (reduce %d, reduce %d) on %s\n",
                    $state->number,
                    $conf->reduce1(),
                    $conf->reduce2(),
                    $conf->symbol()->name
                ));
            }
        }

        for ($x = $state->items; $x !== null; $x = $x->next) {
            $this->context->debug("\t".\trim((string) $x->item)."\n");
        }
        $this->context->debug("\n");

        $i = $j = 0;
        while (true) {
            $s = $state->shifts[$i] ?? null;
            $r = $state->reduce[$j] ?? null;
            if ($s === null && $r === null) {
                break;
            }

            if ($s !== null && ($r === null || $s->through->code < $r->symbol->code)) {
                $str = $s->through->name;
                $this->context->debug(strlen($str) < 8 ? "\t$str\t\t" : "\t$str\t");
                $this->context->debug($s->through->isTerminal ? 'shift' : 'goto');
                $this->context->debug(' '.$s->number);
                if ($s->isReduceOnly()) {
                    $this->context->debug(' and reduce ('.$s->reduce[0]->number.')');
                }
                $this->context->debug("\n");
                $i++;
            } else {
                $str = $r->symbol->isNilSymbol() ? '.' : $r->symbol->name;
                $this->context->debug(strlen($str) < 8 ? "\t$str\t\t" : "\t$str\t");
                if ($r->number === 0) {
                    $this->context->debug("accept\n");
                } elseif ($r->number < 0) {
                    $this->context->debug("error\n");
                } else {
                    $this->context->debug("reduce ($r->number)\n");
                }
                $j++;
            }
        }
        $this->context->debug("\n");
    }

    /**
     * @return void
     */
    protected function printDiagnostics()
    {
        // TODO check expected_srconf
        $expected_srconf = 0;
        if ($this->nsrerr !== $expected_srconf || $this->nrrerr !== 0) {
            $this->context->debug("{$this->context->filename}: there are ");
            if ($this->nsrerr !== $expected_srconf) {
                $this->context->debug(" $this->nsrerr shift/reduce");
                if ($this->nrrerr !== 0) {
                    $this->context->debug(' and');
                }
            }
            if ($this->nrrerr !== 0) {
                $this->context->debug(" $this->nrrerr reduce/reduce");
            }
            $this->context->debug(" conflicts\n");
        }
    }

    /**
     * @return void
     */
    protected function printStatistics()
    {
        if (!$this->context->debug) {
            return;
        }

        $nterms = iterator_count($this->context->terminals);
        $nnonts = iterator_count($this->context->nonterminals);

        $nprods = $this->context->countGrams;
        $totalActs = $this->countActions + $this->countActions2;

        $this->context->debug("\nStatistics for {$this->context->filename}:\n");
        $this->context->debug("\t$nterms terminal symbols\n");
        $this->context->debug("\t$nnonts nonterminal symbols\n");
        $this->context->debug("\t$nprods productions\n");
        $this->context->debug("\t$this->countStates states\n");
        $this->context->debug("\t$this->countNonLeafStates non leaf states\n");
        $this->context->debug("\t$this->nsrerr shift/reduce, $this->nrrerr reduce/reduce conflicts\n");
        // items?
        $this->context->debug("\t$this->countLooks lookahead sets used\n");
        $this->context->debug("\t$this->countActions+$this->countActions2=$totalActs action entries\n");
        // bytes used?
    }
}

stenin-nikita / PHP-Yacc

Generator::computeFollow() C last analyzed 2018-07-30 10:30 UTC

Complexity

Size

Duplication

Importance

How to fix Complexity

Long Method

Duplication Side-by-Side

Filter issues like

Generator::computeFollow() C
last analyzed 2018-07-30 10:30 UTC
