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instance method

IO#<<

ios << obj → ios

VALUE
rb_io_addstr(VALUE io, VALUE str)
{
    rb_io_write(io, str);
    return io;
}

String Output—Writes obj to ios. obj will be converted to a string using to_s.

Example

$stdout << "Hello " << "world!\n"

produces:

Example

Hello world!

See also .write #advise .try_convert #autoclose= also in 4.1 · 4.0 · 3.4 · 3.3 · 3.2 · 3.1