/**********************************************************************
range.c -
$Author: nobu $
$Date: 2005/08/14 15:39:39 $
created at: Thu Aug 19 17:46:47 JST 1993
Copyright (C) 1993-2003 Yukihiro Matsumoto
**********************************************************************/
#include "ruby.h"
VALUE rb_cRange;
static ID id_cmp, id_succ, id_beg, id_end, id_excl;
#define EXCL(r) RTEST(rb_ivar_get((r), id_excl))
#define SET_EXCL(r,v) rb_ivar_set((r), id_excl, (v) ? Qtrue : Qfalse)
static VALUE
range_failed()
{
rb_raise(rb_eArgError, "bad value for range");
return Qnil; /* dummy */
}
static VALUE
range_check(args)
VALUE *args;
{
return rb_funcall(args[0], id_cmp, 1, args[1]);
}
static void
range_init(range, beg, end, exclude_end)
VALUE range, beg, end;
int exclude_end;
{
VALUE args[2];
args[0] = beg;
args[1] = end;
if (!FIXNUM_P(beg) || !FIXNUM_P(end)) {
VALUE v;
v = rb_rescue(range_check, (VALUE)args, range_failed, 0);
if (NIL_P(v)) range_failed();
}
SET_EXCL(range, exclude_end);
rb_ivar_set(range, id_beg, beg);
rb_ivar_set(range, id_end, end);
}
VALUE
rb_range_new(beg, end, exclude_end)
VALUE beg, end;
int exclude_end;
{
VALUE range = rb_obj_alloc(rb_cRange);
range_init(range, beg, end, exclude_end);
return range;
}
/*
* call-seq:
* Range.new(start, end, exclusive=false) => range
*
* Constructs a range using the given start and end. If the third
* parameter is omitted or is false
, the range will include
* the end object; otherwise, it will be excluded.
*/
static VALUE
range_initialize(argc, argv, range)
int argc;
VALUE *argv;
VALUE range;
{
VALUE beg, end, flags;
rb_scan_args(argc, argv, "21", &beg, &end, &flags);
/* Ranges are immutable, so that they should be initialized only once. */
if (rb_ivar_defined(range, id_beg)) {
rb_name_error(rb_intern("initialize"), "`initialize' called twice");
}
range_init(range, beg, end, RTEST(flags));
return Qnil;
}
/*
* call-seq:
* rng.exclude_end? => true or false
*
* Returns true
if rng excludes its end value.
*/
static VALUE
range_exclude_end_p(range)
VALUE range;
{
return EXCL(range) ? Qtrue : Qfalse;
}
/*
* call-seq:
* rng == obj => true or false
*
* Returns true
only if obj is a Range, has equivalent
* beginning and end items (by comparing them with ==
), and has
* the same #exclude_end? setting as rng.
*
* (0..2) == (0..2) #=> true
* (0..2) == Range.new(0,2) #=> true
* (0..2) == (0...2) #=> false
*
*/
static VALUE
range_eq(range, obj)
VALUE range, obj;
{
if (range == obj) return Qtrue;
if (!rb_obj_is_instance_of(obj, rb_obj_class(range)))
return Qfalse;
if (!rb_equal(rb_ivar_get(range, id_beg), rb_ivar_get(obj, id_beg)))
return Qfalse;
if (!rb_equal(rb_ivar_get(range, id_end), rb_ivar_get(obj, id_end)))
return Qfalse;
if (EXCL(range) != EXCL(obj)) return Qfalse;
return Qtrue;
}
static int
r_lt(a, b)
VALUE a, b;
{
VALUE r = rb_funcall(a, id_cmp, 1, b);
if (NIL_P(r)) return Qfalse;
if (rb_cmpint(r, a, b) < 0) return Qtrue;
return Qfalse;
}
static int
r_le(a, b)
VALUE a, b;
{
int c;
VALUE r = rb_funcall(a, id_cmp, 1, b);
if (NIL_P(r)) return Qfalse;
c = rb_cmpint(r, a, b);
if (c == 0) return INT2FIX(0);
if (c < 0) return Qtrue;
return Qfalse;
}
/*
* call-seq:
* rng.eql?(obj) => true or false
*
* Returns true
only if obj is a Range, has equivalent
* beginning and end items (by comparing them with #eql?), and has the same
* #exclude_end? setting as rng.
*
* (0..2) == (0..2) #=> true
* (0..2) == Range.new(0,2) #=> true
* (0..2) == (0...2) #=> false
*
*/
static VALUE
range_eql(range, obj)
VALUE range, obj;
{
if (range == obj) return Qtrue;
if (!rb_obj_is_instance_of(obj, rb_obj_class(range)))
return Qfalse;
if (!rb_eql(rb_ivar_get(range, id_beg), rb_ivar_get(obj, id_beg)))
return Qfalse;
if (!rb_eql(rb_ivar_get(range, id_end), rb_ivar_get(obj, id_end)))
return Qfalse;
if (EXCL(range) != EXCL(obj)) return Qfalse;
return Qtrue;
}
/*
* call-seq:
* rng.hash => fixnum
*
* Generate a hash value such that two ranges with the same start and
* end points, and the same value for the "exclude end" flag, generate
* the same hash value.
*/
static VALUE
range_hash(range)
VALUE range;
{
long hash = EXCL(range);
VALUE v;
v = rb_hash(rb_ivar_get(range, id_beg));
hash ^= v << 1;
v = rb_hash(rb_ivar_get(range, id_end));
hash ^= v << 9;
hash ^= EXCL(range) << 24;
return LONG2FIX(hash);
}
static VALUE
str_step(args)
VALUE *args;
{
return rb_str_upto(args[0], args[1], EXCL(args[2]));
}
static void
range_each_func(range, func, v, e, arg)
VALUE range;
void (*func) _((VALUE, void*));
VALUE v, e;
void *arg;
{
int c;
if (EXCL(range)) {
while (r_lt(v, e)) {
(*func)(v, arg);
v = rb_funcall(v, id_succ, 0, 0);
}
}
else {
while (RTEST(c = r_le(v, e))) {
(*func)(v, arg);
if (c == INT2FIX(0)) break;
v = rb_funcall(v, id_succ, 0, 0);
}
}
}
static VALUE
step_i(i, iter)
VALUE i;
long *iter;
{
iter[0]--;
if (iter[0] == 0) {
rb_yield(i);
iter[0] = iter[1];
}
return Qnil;
}
/*
* call-seq:
* rng.step(n=1) {| obj | block } => rng
*
* Iterates over rng, passing each nth element to the block. If
* the range contains numbers or strings, natural ordering is used. Otherwise
* step
invokes succ
to iterate through range
* elements. The following code uses class Xs
, which is defined
* in the class-level documentation.
*
* range = Xs.new(1)..Xs.new(10)
* range.step(2) {|x| puts x}
* range.step(3) {|x| puts x}
*
* produces:
*
* 1 x
* 3 xxx
* 5 xxxxx
* 7 xxxxxxx
* 9 xxxxxxxxx
* 1 x
* 4 xxxx
* 7 xxxxxxx
* 10 xxxxxxxxxx
*/
static VALUE
range_step(argc, argv, range)
int argc;
VALUE *argv;
VALUE range;
{
VALUE b, e, step;
long unit;
b = rb_ivar_get(range, id_beg);
e = rb_ivar_get(range, id_end);
if (rb_scan_args(argc, argv, "01", &step) == 0) {
step = INT2FIX(1);
}
unit = NUM2LONG(step);
if (unit < 0) {
rb_raise(rb_eArgError, "step can't be negative");
}
if (FIXNUM_P(b) && FIXNUM_P(e)) { /* fixnums are special */
long end = FIX2LONG(e);
long i;
if (unit == 0) rb_raise(rb_eArgError, "step can't be 0");
if (!EXCL(range)) end += 1;
for (i=FIX2LONG(b); i rng
*
* Iterates over the elements rng, passing each in turn to the
* block. You can only iterate if the start object of the range
* supports the +succ+ method (which means that you can't iterate over
* ranges of +Float+ objects).
*
* (10..15).each do |n|
* print n, ' '
* end
*
* produces:
*
* 10 11 12 13 14 15
*/
static VALUE
range_each(range)
VALUE range;
{
VALUE beg, end;
beg = rb_ivar_get(range, id_beg);
end = rb_ivar_get(range, id_end);
if (!rb_respond_to(beg, id_succ)) {
rb_raise(rb_eTypeError, "can't iterate from %s",
rb_obj_classname(beg));
}
if (FIXNUM_P(beg) && FIXNUM_P(end)) { /* fixnums are special */
long lim = FIX2LONG(end);
long i;
if (!EXCL(range)) lim += 1;
for (i=FIX2LONG(beg); i obj
* rng.begin => obj
*
* Returns the first object in rng.
*/
static VALUE
range_first(range)
VALUE range;
{
return rb_ivar_get(range, id_beg);
}
/*
* call-seq:
* rng.end => obj
* rng.last => obj
*
* Returns the object that defines the end of rng.
*
* (1..10).end #=> 10
* (1...10).end #=> 10
*/
static VALUE
range_last(range)
VALUE range;
{
return rb_ivar_get(range, id_end);
}
VALUE
rb_range_beg_len(range, begp, lenp, len, err)
VALUE range;
long *begp, *lenp;
long len;
int err;
{
long beg, end, b, e;
if (!rb_obj_is_kind_of(range, rb_cRange)) return Qfalse;
beg = b = NUM2LONG(rb_ivar_get(range, id_beg));
end = e = NUM2LONG(rb_ivar_get(range, id_end));
if (beg < 0) {
beg += len;
if (beg < 0) goto out_of_range;
}
if (err == 0 || err == 2) {
if (beg > len) goto out_of_range;
if (end > len) end = len;
}
if (end < 0) end += len;
if (!EXCL(range)) end++; /* include end point */
len = end - beg;
if (len < 0) len = 0;
*begp = beg;
*lenp = len;
return Qtrue;
out_of_range:
if (err) {
rb_raise(rb_eRangeError, "%ld..%s%ld out of range",
b, EXCL(range)? "." : "", e);
}
return Qnil;
}
/*
* call-seq:
* rng.to_s => string
*
* Convert this range object to a printable form.
*/
static VALUE
range_to_s(range)
VALUE range;
{
VALUE str, str2;
str = rb_obj_as_string(rb_ivar_get(range, id_beg));
str2 = rb_obj_as_string(rb_ivar_get(range, id_end));
str = rb_str_dup(str);
rb_str_cat(str, "...", EXCL(range)?3:2);
rb_str_append(str, str2);
OBJ_INFECT(str, str2);
return str;
}
/*
* call-seq:
* rng.inspect => string
*
* Convert this range object to a printable form (using
* inspect
to convert the start and end
* objects).
*/
static VALUE
range_inspect(range)
VALUE range;
{
VALUE str, str2;
str = rb_inspect(rb_ivar_get(range, id_beg));
str2 = rb_inspect(rb_ivar_get(range, id_end));
str = rb_str_dup(str);
rb_str_cat(str, "...", EXCL(range)?3:2);
rb_str_append(str, str2);
OBJ_INFECT(str, str2);
return str;
}
/*
* call-seq:
* rng === obj => true or false
* rng.member?(val) => true or false
* rng.include?(val) => true or false
*
* Returns true
if obj is an element of
* rng, false
otherwise. Conveniently,
* ===
is the comparison operator used by
* case
statements.
*
* case 79
* when 1..50 then print "low\n"
* when 51..75 then print "medium\n"
* when 76..100 then print "high\n"
* end
*
* produces:
*
* high
*/
static VALUE
range_include(range, val)
VALUE range, val;
{
VALUE beg, end;
beg = rb_ivar_get(range, id_beg);
end = rb_ivar_get(range, id_end);
if (r_le(beg, val)) {
if (EXCL(range)) {
if (r_lt(val, end)) return Qtrue;
}
else {
if (r_le(val, end)) return Qtrue;
}
}
return Qfalse;
}
/* A Range
represents an interval---a set of values with a
* start and an end. Ranges may be constructed using the
* s..
e and
* s...
e literals, or with
* Range::new
. Ranges constructed using ..
* run from the start to the end inclusively. Those created using
* ...
exclude the end value. When used as an iterator,
* ranges return each value in the sequence.
*
* (-1..-5).to_a #=> []
* (-5..-1).to_a #=> [-5, -4, -3, -2, -1]
* ('a'..'e').to_a #=> ["a", "b", "c", "d", "e"]
* ('a'...'e').to_a #=> ["a", "b", "c", "d"]
*
* Ranges can be constructed using objects of any type, as long as the
* objects can be compared using their <=>
operator and
* they support the succ
method to return the next object
* in sequence.
*
* class Xs # represent a string of 'x's
* include Comparable
* attr :length
* def initialize(n)
* @length = n
* end
* def succ
* Xs.new(@length + 1)
* end
* def <=>(other)
* @length <=> other.length
* end
* def to_s
* sprintf "%2d #{inspect}", @length
* end
* def inspect
* 'x' * @length
* end
* end
*
* r = Xs.new(3)..Xs.new(6) #=> xxx..xxxxxx
* r.to_a #=> [xxx, xxxx, xxxxx, xxxxxx]
* r.member?(Xs.new(5)) #=> true
*
* In the previous code example, class Xs
includes the
* Comparable
module. This is because
* Enumerable#member?
checks for equality using
* ==
. Including Comparable
ensures that the
* ==
method is defined in terms of the <=>
* method implemented in Xs
.
*
*/
void
Init_Range()
{
rb_cRange = rb_define_class("Range", rb_cObject);
rb_include_module(rb_cRange, rb_mEnumerable);
rb_define_method(rb_cRange, "initialize", range_initialize, -1);
rb_define_method(rb_cRange, "==", range_eq, 1);
rb_define_method(rb_cRange, "===", range_include, 1);
rb_define_method(rb_cRange, "eql?", range_eql, 1);
rb_define_method(rb_cRange, "hash", range_hash, 0);
rb_define_method(rb_cRange, "each", range_each, 0);
rb_define_method(rb_cRange, "step", range_step, -1);
rb_define_method(rb_cRange, "first", range_first, 0);
rb_define_method(rb_cRange, "last", range_last, 0);
rb_define_method(rb_cRange, "begin", range_first, 0);
rb_define_method(rb_cRange, "end", range_last, 0);
rb_define_method(rb_cRange, "to_s", range_to_s, 0);
rb_define_method(rb_cRange, "inspect", range_inspect, 0);
rb_define_method(rb_cRange, "exclude_end?", range_exclude_end_p, 0);
rb_define_method(rb_cRange, "member?", range_include, 1);
rb_define_method(rb_cRange, "include?", range_include, 1);
id_cmp = rb_intern("<=>");
id_succ = rb_intern("succ");
id_beg = rb_intern("begin");
id_end = rb_intern("end");
id_excl = rb_intern("excl");
}