A command that draws — everything except move and close, which position
the pen rather than mark the page.
Having the narrower type is what lets the operations that walk segments
(reversing one, splitting one) be exhaustive over four kinds instead of
carrying two cases that cannot arise.
A command that draws — everything except
moveandclose, which position the pen rather than mark the page.Having the narrower type is what lets the operations that walk segments (reversing one, splitting one) be exhaustive over four kinds instead of carrying two cases that cannot arise.