Implement Array#slice!
MODIFY
mrbgems/mruby-array-ext/src/array.c
mrbgems/mruby-array-ext/src/array.c
@@ -149,6 +149,81 @@ mrb_ary_to_h(mrb_state *mrb, mrb_value ary)
return hash;
}
+/*
+ * call-seq:
+ * ary.slice!(index) -> obj or nil
+ * ary.slice!(start, length) -> new_ary or nil
+ * ary.slice!(range) -> new_ary or nil
+ *
+ * Deletes the element(s) given by an +index+ (optionally up to +length+
+ * elements) or by a +range+.
+ *
+ * Returns the deleted object (or objects), or +nil+ if the +index+ is out of
+ * range.
+ *
+ * a = [ "a", "b", "c" ]
+ * a.slice!(1) #=> "b"
+ * a #=> ["a", "c"]
+ * a.slice!(-1) #=> "c"
+ * a #=> ["a"]
+ * a.slice!(100) #=> nil
+ * a #=> ["a"]
+ */
+
+static mrb_value
+mrb_ary_slice_bang(mrb_state *mrb, mrb_value self)
+{
+ struct RArray *a = mrb_ary_ptr(self);
+ mrb_int i, len;
+ mrb_value index;
+ mrb_value val;
+ mrb_value *ptr;
+ mrb_value ary;
+
+ mrb_ary_modify(mrb, a);
+
+ if (mrb_get_args(mrb, "o|i", &index, &len) == 1) {
+ switch (mrb_type(index)) {
+ case MRB_TT_RANGE:
+ if (mrb_range_beg_len(mrb, index, &i, &len, a->len, TRUE) == 1) {
+ goto delete_pos_len;
+ }
+ else {
+ return mrb_nil_value();
+ }
+ case MRB_TT_FIXNUM:
+ val = mrb_funcall(mrb, self, "delete_at", 1, index);
+ return val;
+ default:
+ val = mrb_funcall(mrb, self, "delete_at", 1, index);
+ return val;
+ }
+ }
+
+ i = mrb_fixnum(index);
+ delete_pos_len:
+ if (i < 0) i += a->len;
+ if (i < 0 || a->len < i) return mrb_nil_value();
+ if (len < 0) return mrb_nil_value();
+ if (a->len == i) return mrb_ary_new(mrb);
+ if (len > a->len - i) len = a->len - i;
+
+ ary = mrb_ary_new_capa(mrb, len);
+
+ for (mrb_int j = i, k = 0; k < len; ++j, ++k) {
+ mrb_ary_push(mrb, ary, a->ptr[j]);
+ }
+
+ ptr = a->ptr + i;
+ for (mrb_int j = i; j <= a->len - len; ++j) {
+ *ptr = *(ptr+len);
+ ++ptr;
+ }
+
+ mrb_ary_resize(mrb, self, a->len - len);
+ return ary;
+}
+
void
mrb_mruby_array_ext_gem_init(mrb_state* mrb)
{
@@ -159,6 +234,7 @@ mrb_mruby_array_ext_gem_init(mrb_state* mrb)
mrb_define_method(mrb, a, "rassoc", mrb_ary_rassoc, MRB_ARGS_REQ(1));
mrb_define_method(mrb, a, "values_at", mrb_ary_values_at, MRB_ARGS_ANY());
mrb_define_method(mrb, a, "to_h", mrb_ary_to_h, MRB_ARGS_REQ(0));
+ mrb_define_method(mrb, a, "slice!", mrb_ary_slice_bang, MRB_ARGS_ANY());
}
void

MODIFY
mrbgems/mruby-array-ext/test/array.rb
mrbgems/mruby-array-ext/test/array.rb
@@ -328,3 +328,27 @@ assert("Array#dig") do
assert_nil(h.dig(2, 0))
assert_raise(TypeError) {h.dig(:a)}
end
+
+assert("Array#slice!") do
+ a = [1, 2, 3]
+ b = a.slice!(0)
+ c = [1, 2, 3, 4, 5]
+ d = c.slice!(0, 2)
+ e = [1, 2, 3, 4, 5]
+ f = e.slice!(1..3)
+ g = [1, 2, 3]
+ h = g.slice!(-1)
+ i = [1, 2, 3]
+ j = i.slice!(0, -1)
+
+ assert_equal(a, [2, 3])
+ assert_equal(b, 1)
+ assert_equal(c, [3, 4, 5])
+ assert_equal(d, [1, 2])
+ assert_equal(e, [1, 5])
+ assert_equal(f, [2, 3, 4])
+ assert_equal(g, [1, 2])
+ assert_equal(h, 3)
+ assert_equal(i, [1, 2, 3])
+ assert_equal(j, nil)
+end

Implement Array#slice!