grammar - What's the role of だけの in this sentence?

彼らは工場を建設するだけの資金を持っている。

The translation on Jisho is: "They have enough capital to build a second factory."

Answer

だけ of course mainly means "only", but it has other meanings. clause + だけ can mean "to the degree that ～".

On JGram, the following examples are relevant.

• この本は読むだけの価値がある。
  This book is certainly worth reading.
  (lit. "This book has the value to the extent you read")


• 日本語がこれだけ書ければとてもすばらしいと思います。
  I think it's great that you can write Japanese like this. (or: this much, to this extent)