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0 pointsstinos6y ago0 comments

That actually proves my point. I'm not really good in learning certain facts by heart so if I see a < b < c it is going to take multiple seconds, likely followed by an internet search so add a couple of minutes to that, before I can be 100% sure what it does. I mean, I know what precedence is and I'd probably assume it would be (a < b) < c but that's not going to cut it.

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11 comments · 2 top-level

aktuel6y ago· 7 in thread

Just program in assembler then.

Honestly, Python's way is the only sane way to parse this. This is how a human who never programmed before with some knowledge of math would understand it.

Everyone's else mind is just corrupted by broken legacy languages.

apricot6y ago

I sometimes teach programming to beginners who have some knowledge of math. A common mistake they make is to write compound conditionals like this:

    if a == 2 or 3:
        do stuff

because that's how they would write it in math. Does that mean Python is broken and should support that construct as well?

edflsafoiewq6y ago

I believe COBOL supports this.

maest6y ago

Even if Python's way was the only sane way of doing it (view which, btw, denotes having narrow experience with programming languages), that's irrelevant. GP's point was that different languages use different rules so, unless you use brackets, you won't easily know which precedence rules get applied.

Retric6y ago

Python’s edge cases are just as odd as every other language

  >>> a=16
  >>> a*a is a*a
  True
  >>> a=17
  >>> a*a is a*a
  False

“is”, “==“, and “=“ are all very different and none of them match their mathematical equivalents very well.

dhosek6y ago

Not really familiar with Python. Do you know why the second statement evaluates as false?

3 more replies

xyproto6y ago

Math notation is just one of many possible notations, though. And math notation is not static throughout history.

aktuel6y ago

True. But the syntax of almost all other languages are derived from the same basic math syntax we use commonly for at least since programming languages are a thing.

shkkmo6y ago· 2 in thread

When you use a tricky language feature to improve readability, you can just add a comment to the link some piece of documentation for that behavior. It is still a trade-off, but it saves a bit of time and whenever I come across a place where past me did this, I am always appreciative.

stinosOP6y ago

Depends. For obscure behavior features, ok, for 'language features' I'm probably still going to pass. Because in this example case that would come down do

  # See stackoverflow/highlyupvoted/wtf/does/python/do/here
  # This is the same as (a < b) < c.
  x = a < b < c

whih is not clearer, not easier to parse and not faster to read and harder to maintain (leads to rot easily when variable names change) than the non-ambiguous other choice.

shkkmo6y ago

I would have skipped that second line and just left the line with the documentation link. If you are going to provide the equivalent code in a comment, you might as well just use the equivalent code.

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