Re: Style, *again*

[Abigail-II]

in reply to Re: Re: Style, *again*
in thread Style, *again*

Thanks for the annotated list. I don't always make the same decisions, but it's interesting to see where people take an different approach, and why they do that. One question I have, you write:

Logical order in comparisons: $foo == 4, but never 4 == $foo

It's inside a bunch of rules for which you give "Normal linguistics/interpunction." as a reason. I don't think that applies for the quoted rule - I'd like to know why you would never write 4 == $foo.

Abigail

[Juerd]

It's inside a bunch of rules for which you give "Normal linguistics/interpunction." as a reason. I don't think that applies for the quoted rule - I'd like to know why you would never write 4 == $foo.

It's kind of normal to put the topic (subject) first. 4 is not the topic, because you already know what 4 is. $foo is what you are unsure about.

Consider these sentences:
"If the image on the cover is a camel, the book is probably Programming Perl."
"If a camel is the image on the cover, the book is probably Programming Perl."
"If foo is 4, ..."
"If 4 is foo, ..."

The camel is constant, the image can be anything.

Juerd
- http://juerd.nl/
- [e-mail] (do not use).

[Abigail-II]

I see.

I do sometimes write the constant first, because I want to reduce the amount of punctuation. If you write:

    foo $x, $y == 4

then foo isn't called with arguments $x and $y. You'd need to write that as:

    foo ($x, $y) == 4

Or

    4 == foo $x, $y

And since == is a symmetric operation (assuming it's not overloaded), I don't feel strongly for the "topic first" argument. But I can see your point.

Abigail

[demerphq]

And since == is a symmetric operation

Which is the reason I often put the constant first. Turning an == into an = accidentally results in a non symmetric operation which is illegal when the left side is a constant. Which helps catch silly mistakes that the compiler doesnt notice (like in the conditional part of a ternary op.)


---
demerphq

_{<Elian> And I do take a kind of perverse pleasure in having an OO assembly language...}

[oylee]

It does make more sense when you read it out loud, but since there's no semantic difference, it sometimes helps to place immutables as the first operand since then you'll get a compiler error out of the simple typo:

unless ($foo = 4) {
   ... argle blougat blopf ...
}

when it looks like this:

unless (4 = $foo) {
   ... womble ...
}