magcius

static BOOL
inside_segment(int v, int v1, int v2)
{
    if (v1 < 0 && v2 < 0) /* line */
        return TRUE;
    else if (v1 < 0)      /* ray */
        return v <= v2;
    else if (v2 < 0)      /* ray */
        return v >= v1;
    else                  /* line segment */

magcius

Parsley Tutorial

From Regular Expressions To Grammars

Parsley is a pattern matching and parsing tool for Python programmers.

magcius

Parsley Tutorial

Let's parse it up with Parsley. Following the standard example of other parsing frameworks, we're going to build a standard mathematical expression parser. Unlike other frameworks like PyParsing, Parsley grammars are defined in a giant string, rather than a special DSL.

Let's start with something that can interpret a collection of digits, and spit out a number:

import parsley

magcius

/* gcc -o listmode listmode.c $(pkg-config --cflags --libs glib-2.0 libdrm) */

#include <glib.h>
#include <fcntl.h>
#include <stdlib.h>
#include <xf86drm.h>
#include <xf86drmMode.h>

int
main (int argc, char **argv)

magcius

/* gcc -o displaybuffer displaybuffer.c $(pkg-config --cflags --libs glib-2.0 libdrm) */

#include <glib.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <xf86drm.h>
#include <xf86drmMode.h>

int

magcius

/* gcc -o listconnectors listconnectors.c $(pkg-config --cflags --libs glib-2.0 libdrm) */

#include <glib.h>
#include <fcntl.h>
#include <stdlib.h>
#include <xf86drm.h>
#include <xf86drmMode.h>

int
main (int argc, char **argv)

magcius

/* gcc -o listconnectors listconnectors.c $(pkg-config --cflags --libs glib-2.0 libdrm) */

#include <glib.h>
#include <fcntl.h>
#include <stdlib.h>
#include <xf86drm.h>
#include <xf86drmMode.h>

int
main (int argc, char **argv)

magcius

const Lang = imports.lang;
const Signals = imports.signals;

const Tweener = imports.tweener.tweener;
const Clutter = imports.gi.Clutter;

Clutter.init(null);

let white = Clutter.Color.get_static(Clutter.StaticColor.WHITE);

magcius

#include <sdl.h>

struct _EventFuncs {
    void (*on_keydown) (char key, void *user_data);
    void (*on_loop) (void *user_data);
};

typedef struct _EventFuncs EventFucs;

void event_loop(EventFuncs *event_funcs, void *user_data) {

magcius

#include <cairo/cairo.h>
#include <math.h>

static void
draw_region (cairo_t        *cr,
             cairo_region_t *region)
{
  cairo_rectangle_int_t box;
  int n_boxes, i;