ate_expr :: Parser (AST' Text)
summate_expr =
    reserved "summate"
    *> (Summate
        <$> identifier
        <*  symbol "from"
        <*> expr
        <*  symbol "to"
        <*> expr
        <*> semiblockExpr
        )

pr
summate_expr :: Parser (AST' Text)
summate_expr =
    reserved "summate"
    *> (Summate
        <$> identifier
        <*  symbol "from"
        <*> expr
        <*  symbol "to"
        <*> expr
        <*> semiblockExpr
        )
summate_expr =
    reserved "summate"
    *> (Summate
        <$> identifier
        <*  symbol "from"
        <*> expr
        <*  symbol "to"
        <*> expr
        <*> semiblockExpr
        )