Beyond all the texts suggested by the previous poster, a really good source of learning is this very site. Post some snippets and see what the replies say. Whenever there's a golf challenge, read every single node. Try and read the replies of some of the more experienced monks, especially what they've said before. I know that I've learned a lot by reading tilly's nodes on design theory. Hopefully, some have learned a bit from my nodes on the same topic(s).

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We are the carpenters and bricklayers of the Information Age.

Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.