Surely "1337" is the same as 1337, right?

bleistift2@sopuli.xyz to Programmer Humor@programming.dev – 524 points –

Meme transcription:

Panel 1: Bilbo Baggins ponders, “After all… why should I care about the difference between int and String?

Panel 2: Bilbo Baggins is revealed to be an API developer. He continues, “JSON is always String, anyways…”

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I’m not sure if you’re getting it, so I’ll explain just in case.

In computer science a few conventions have emerged on how numbers should be interpreted, depending on how they start:

  • decimal (the usual system with digits from 0 to 9): no prefix
  • binary (digits 0 and 1): prefix 0b, so 0b1001110
  • octal (digits 0 through 7): prefix 0, so 0116
  • hexadecimal (digits 0 through 9 and then A through E): prefix 0x, so 0x8E

If your zip code starts with 9, it won’t be interpreted as octal. You’re fine.

Well, you're right. I wasn't getting it, but I've also never seen any piece of software that would treat a single leading zero as octal. That's just a recipe for disaster, and it should use 0o116 to be unambiguous

(I am a software engineer, but was assuming you meant it was hardcoded to parse as octal, not some weird auto-detect)

I’ve also never seen any piece of software that would treat a single leading zero as octal

I thought JavaScript did that, but it turns out it doesn’t. I thought Java did that, but it turns out it doesn’t. Python did it until version 2.7: https://docs.python.org/2.7/library/functions.html#int. C still does it: https://en.cppreference.com/w/c/string/byte/strtol

Interesting that strtol in C does that. I've always explicitly passed in base 10 or 16, but I didn't know it would auto-detect if you passed 0. TIL.

It's been a long time, but I'm pretty sure C treats a leading zero as octal in source code. PHP and Node definitely do. Yes, it's a bad convention. It's much worse if that's being done by a runtime function that parses user input, though. I'm pretty sure I've seen that somewhere in the past, but no idea where. Doesn't seem likely to be common.

PHP and Node definitely do.

Node doesn’t.

> parseInt('077')
77
  1. If the input string, with leading whitespace and possible +/- signs removed, begins with 0x or 0X (a zero, followed by lowercase or uppercase X), radix is assumed to be 16 and the rest of the string is parsed as a hexadecimal number.
  2. If the input string begins with any other value, the radix is 10 (decimal).

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/parseInt

You seem to have missed the important phrase "in source code", as well as the entire second part of my comment discussing that runtime functions that parse user input are different.