Function wrap

flag.go:658–702

Wraps the string `s` to a maximum width `w` with leading indent `i`. The first line is not indented (this is assumed to be done by caller). Pass `w` == 0 to do no wrapping

(i, w int, s string)

// `i`. The first line is not indented (this is assumed to be done by
// caller). Pass `w` == 0 to do no wrapping
func wrap(i, w int, s string) string {
	if w == 0 {
		return strings.Replace(s, "\n", "\n"+strings.Repeat(" ", i), -1)
	}

	// space between indent i and end of line width w into which
	// we should wrap the text.
	wrap := w - i

	var r, l string

	// Not enough space for sensible wrapping. Wrap as a block on
	// the next line instead.
	if wrap < 24 {
		i = 16
		wrap = w - i
		r += "\n" + strings.Repeat(" ", i)
	}
	// If still not enough space then don't even try to wrap.
	if wrap < 24 {
		return strings.Replace(s, "\n", r, -1)
	}

	// Try to avoid short orphan words on the final line, by
	// allowing wrapN to go a bit over if that would fit in the
	// remainder of the line.
	slop := 5
	wrap = wrap - slop

	// Handle first line, which is indented by the caller (or the
	// special case above)
	l, s = wrapN(wrap, slop, s)
	r = r + strings.Replace(l, "\n", "\n"+strings.Repeat(" ", i), -1)

	// Now wrap the rest
	for s != "" {
		var t string

		t, s = wrapN(wrap, slop, s)
		r = r + "\n" + strings.Repeat(" ", i) + strings.Replace(t, "\n", "\n"+strings.Repeat(" ", i), -1)
	}

	return r

}

// FlagUsagesWrapped returns a string containing the usage information
// for all flags in the FlagSet. Wrapped to `cols` columns (0 for no