view Parser/grammar1.c @ 87690:66c1c9f32567 default tip

Add use_weakref option to functools.lru_cache The use_weakref option makes lru_cache create weak references to the function arguments when creating the cache key, which prevents them from staying in the memory forever even after all other references to them are gone. This is a proof of concept for http://bugs.python.org/issue19859
author Radomir Dopieralski <devel@sheep.art.pl>
date Tue, 03 Dec 2013 16:02:48 +0100
parents e7f6cef7a4cc
children
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/* Grammar subroutines needed by parser */

#include "Python.h"
#include "pgenheaders.h"
#include "grammar.h"
#include "token.h"

/* Return the DFA for the given type */

dfa *
PyGrammar_FindDFA(grammar *g, int type)
{
    dfa *d;
#if 1
    /* Massive speed-up */
    d = &g->g_dfa[type - NT_OFFSET];
    assert(d->d_type == type);
    return d;
#else
    /* Old, slow version */
    int i;

    for (i = g->g_ndfas, d = g->g_dfa; --i >= 0; d++) {
        if (d->d_type == type)
            return d;
    }
    assert(0);
    /* NOTREACHED */
#endif
}

const char *
PyGrammar_LabelRepr(label *lb)
{
    static char buf[100];

    if (lb->lb_type == ENDMARKER)
        return "EMPTY";
    else if (ISNONTERMINAL(lb->lb_type)) {
        if (lb->lb_str == NULL) {
            PyOS_snprintf(buf, sizeof(buf), "NT%d", lb->lb_type);
            return buf;
        }
        else
            return lb->lb_str;
    }
    else if (lb->lb_type < N_TOKENS) {
        if (lb->lb_str == NULL)
            return _PyParser_TokenNames[lb->lb_type];
        else {
            PyOS_snprintf(buf, sizeof(buf), "%.32s(%.32s)",
                _PyParser_TokenNames[lb->lb_type], lb->lb_str);
            return buf;
        }
    }
    else {
        Py_FatalError("invalid label");
        return NULL;
    }
}