Because user commands and attributes only have one parser invocation,
they always parse all their arguments in a tuple, unlike tactics which
have several parser invocations. To prevent issues where we call the
parser multiple times or zero times, we use the Parse1 alias whose
constructor encourages exactly one call to parse.
Because user commands and attributes only have one parser invocation, they always parse all their arguments in a tuple, unlike tactics which have several parser invocations. To prevent issues where we call the parser multiple times or zero times, we use the
Parse1alias whose constructor encourages exactly one call toparse.