Ash Framework: Hard to read regex (page 48)

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The regex on page 48 is hard to read:

~r/(^https:\/\/|\/images\/).+(\.png|\.jpg)$/

It can be improved by changing the delimiters which means that you don’t have to escape all the forward slashes. Like so:

~r"(^https://|/images/).+(\.png|\.jpg)$"

1 Like
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Oh that’s a great idea! Thank you, we’ll do that :slight_smile:

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I don’t think that’s quite right. Going through the book today, testing the validations, the above solution doesn’t handle /images quite right. It also results in a warning on elixir 1.18/otp27.

I suggest

~S{(^https://|^/images/).+(\.png|\.jpg)$}

Note the additional ^ anchor on /images, and syntax as suggested by the warning.

Great book so far though!

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From what I’ve heard the warning only appears on OTP 28, but I haven’t even managed to get the app to compile using it due to dependencies that don’t support it :sweat_smile: it’s definitely on my list of things to fix before the book goes into print.

And a good point about the extra ^, I hadn’t realized that was missing and will fix, thank you :slight_smile: Or even move it outside the () for a bit of clarity!

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fwiw, I’m on otp27

Erlang/OTP 27 [erts-15.2.7] [source] [64-bit] [smp:8:8] [ds:8:8:10] [async-threads:1] [jit]

Elixir 1.18.4 (compiled with Erlang/OTP 27)