SRC_TPL1          374 core/syntax.y      | n:arg-name        { SRC_TPL1(n) }
SRC_TPL1          376 core/syntax.y  optional = '|' -        { SRC_TPL1(PN_NUM('|')) }
SRC_TPL1          377 core/syntax.y  arg-rest = "..." -      { SRC_TPL1(PN_NUM('.')) }
SRC_TPL1          378 core/syntax.y  arg-sep = '.' -         { SRC_TPL1(PN_NUM('.')) } #x,y... ignore rest