func (b Builder) String() string {
	return b.s
}
String returns the generated string.
package colorstring
import (
	"fmt"
)
type Builder struct {
	s string
}
func NewBuilder() *Builder {
	return &Builder{}
}
func (b *Builder) add(colorFunc ColorfFunc, format string, v ...interface{}) *Builder {
	if colorFunc == nil {
		b.s += fmt.Sprintf(format, v...)
	} else {
		b.s += colorFunc(format, v...)
	}
	return b
}
func (b *Builder) NewLine() *Builder {
	return b.add(nil, "\n")
}
func (b *Builder) Plain(format string, v ...interface{}) *Builder {
	return b.add(nil, format, v...)
}
func (b *Builder) Black(format string, v ...interface{}) *Builder {
	return b.add(Black, format, v...)
}
func (b *Builder) Red(format string, v ...interface{}) *Builder {
	return b.add(Red, format, v...)
}
func (b *Builder) Green(format string, v ...interface{}) *Builder {
	return b.add(Green, format, v...)
}
func (b *Builder) Yellow(format string, v ...interface{}) *Builder {
	return b.add(Yellow, format, v...)
}
func (b *Builder) Blue(format string, v ...interface{}) *Builder {
	return b.add(Blue, format, v...)
}
func (b *Builder) Magenta(format string, v ...interface{}) *Builder {
	return b.add(Magenta, format, v...)
}
func (b *Builder) Cyan(format string, v ...interface{}) *Builder {
	return b.add(Cyan, format, v...)
}