Point free style in TypeScript

point-free.ts

    interface Transaction {
      amount: number;
    }

    class Test {
      private const BIG_AMOUNT = 10;  
        
      public getPositiveTransactions(transactions: Transaction[]) {
        // point free
        return transactions.filter(this.isPositive);
         
        // not point free
        // return transactions.filter((transaction: Transaction) => transaction.amount > 0));
      }

      public getBigTransactions(transactions: Transaction[]) {
        // point free
        return transactions.filter(this.moreThan(BIG_AMOUNT));

        // not point free
        // return transactions.filter((transaction: any) => transaction.amount > BIG_AMOUNT);
      }

      private isPositive(transaction: Transaction) {
        return transactions.amount > 0;
      }

      private moreThan(amount: number) {
        return (transaction: Transaction) => {
          return transactions.amount > amount;
        }
      }
    }