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instance method

StringScanner#pos=

(::Integer) -> ::Integer

pos = n → n

pointer = n → n

static VALUE
strscan_set_pos(VALUE self, VALUE v)
{
    struct strscanner *p;
    rb_len_t i;

    GET_SCANNER(self, p);
    i = NUM2LEN(v);
    if (i < 0) i += S_LEN(p);
    if (i < 0) rb_raise(rb_eRangeError, "index out of range");
    if (i > S_LEN(p)) rb_raise(rb_eRangeError, "index out of range");
    p->curr = i;
    return LEN2NUM(i);
}

Sets the byte position and the character position; returns n.

Does not affect match values.

For non-negative n, sets the position to n:

Example

scanner = StringScanner.new(HIRAGANA_TEXT)
scanner.string  # => "こんにちは"
scanner.pos = 3 # => 3
scanner.rest    # => "んにちは"
scanner.charpos # => 1

For negative n, counts from the end of the stored string:

Example

scanner.pos = -9 # => -9
scanner.pos      # => 6
scanner.rest     # => "にちは"
scanner.charpos  # => 2

See also #pos #post_match #pointer= #pre_match also in 4.0 · 3.4 · 3.3 · 3.2 · 3.1 · 3.0

‹ prev#pos next ›#post_match