func (b *Buffer) Truncate(n int) {
	if n == 0 {
		b.Reset()
		return
	}
	b.lastRead = opInvalid
	if n < 0 || n > b.Len() {
		panic("bytes.Buffer: truncation out of range")
	}
	b.buf = b.buf[:b.off+n]
}

// Reset resets the buffer to be empty,
// but it retains the underlying storage for use by future writes.
// Reset is the same as [Buffer.Truncate](0).

The conversion always yields a valid value; there is no indication of overflow.
</li>
<li>
When converting a floating-point number to an integer, the fraction is discarded
(truncation towards zero).
</li>
<li>
When converting an integer or floating-point number to a floating-point type,
or a complex number to another complex type, the result value is rounded

		err:  ErrHeader,
	}, {
		// BSD tar v3.1.2 rejects a PAX path with NUL in the value, while
		// GNU tar v1.27.1 simply truncates at first NUL.
		// We emulate the behavior of BSD since it is strange doing NUL
		// truncations since PAX records are length-prefix strings instead
		// of NUL-terminated C-strings.
		file: "testdata/pax-nul-path.tar",
		err:  ErrHeader,
	}, {
		file: "testdata/neg-size.tar",
		err:  ErrHeader,
	}, {

The conversion always yields a valid value; there is no indication of overflow.
</li>
<li>
When converting a <a href="#Numeric_types">floating-point number</a> to an integer, the fraction is discarded
(truncation towards zero).
</li>
<li>
When converting an integer or floating-point number to a floating-point type,
or a <a href="#Numeric_types">complex number</a> to another complex type, the result value is rounded