n_expr :: Parser (AST' Text)
chain_expr =
    reserved "chain"
    *> (Chain
        <$> identifier
        <*> expr
        <*> expr
        <*> semiblockExpr
        )


i
chain_expr :: Parser (AST' Text)
chain_expr =
    reserved "chain"
    *> (Chain
        <$> identifier
        <*> expr
        <*> expr
        <*> semiblockExpr
        )
chain_expr =
    reserved "chain"
    *> (Chain
        <$> identifier
        <*> expr
        <*> expr
        <*> semiblockExpr
        )