set_value

        # IO::Buffer.set_value

(from ruby core)
### Implementation from Buffer
---
    set_value(type, offset, value) -> offset

---

Write to a buffer a `value` of `type` at `offset`. `type` should be one
of symbols described in #get_value.

    buffer = IO::Buffer.new(8)
    #  =>
    # #<IO::Buffer 0x0000555f5c9a2d50+8 INTERNAL>
    # 0x00000000  00 00 00 00 00 00 00 00
    buffer.set_value(:U8, 1, 111)
    # => 1
    buffer
    #  =>
    # #<IO::Buffer 0x0000555f5c9a2d50+8 INTERNAL>
    # 0x00000000  00 6f 00 00 00 00 00 00                         .o......

Note that if the `type` is integer and `value` is Float, the implicit
truncation is performed:

    buffer = IO::Buffer.new(8)
    buffer.set_value(:U32, 0, 2.5)
    buffer
    #   =>
    #  #<IO::Buffer 0x0000555f5c9a2d50+8 INTERNAL>
    #  0x00000000  00 00 00 02 00 00 00 00
    #                       ^^ the same as if we'd pass just integer 2