import (
	"gop/tpl"
	"os"
)

cl := tpl`
expr = termExpr % ("+" | "-")

termExpr = unaryExpr % ("*" | "/")

unaryExpr = operand | "-" unaryExpr

operand = INT | FLOAT | "(" expr ")"
`!

print "> "
for line in os.Stdin {
	e, err := cl.parseExpr(line, nil)
	if err != nil {
		print "${err}\n> "
	} else {
		tpl.dump e
		print "> "
	}
}