Re^2: Pointers and References

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Re^3: Pointers and References by GrandFather (Saint) on Nov 23, 2020 at 19:57 UTC
Anonymous Monk is quite right. The do block is there to wrap up a "main". I don't usually bother, but in this case a previous iteration of the sub had variables with the same name as were in the main block of code so I used the do block to limit the scope of those variables. As a general thing avoiding global variables is good. In larger scripts I write a formal `sub main` to ensure the only global variables are deliberate and explicit. So the do block is a light weight version of that practice that remained somewhat beyond its use by date, but a useful discussion point as it turns out. Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond	[reply] [d/l]
Re^4: Pointers and References by LanX (Saint) on Nov 23, 2020 at 21:16 UTC
> I used the do block to limit the scope of those variables. maybe consider a "`naked BLOCK`" instead of `do BLOCK` to limit the scope. `{ my $limited_in_scope; }` [download] Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply] [d/l] [select]
Re^5: Pointers and References by GrandFather (Saint) on Nov 23, 2020 at 21:56 UTC
Sure. For me naked blocks in C++ and similar languages are almost universally scope limiting blocks for process locking of various sorts. I tend to not use them in other contexts and that bleeds through to Perl. And again, for trivial code like this I wouldn't usually bother, but I was "belt and braces" checking the example code in an earlier iteration and forgot to remove the block. Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond	[reply]
Re^6: Pointers and References by davido (Cardinal) on Nov 25, 2020 at 18:11 UTC
Re^4: Pointers and References by Bod (Parson) on Nov 23, 2020 at 21:40 UTC
Where I want to explicitly show that a variable is deliberately global, I declare it with `our`.	[reply] [d/l]
Re^5: Pointers and References by GrandFather (Saint) on Nov 23, 2020 at 22:02 UTC
I almost never use our. Usually when I say global I mean global to the file and I might prefix the variable name with a g. our tells you something is "global" where you declare the variable, but it doesn't tell you that where you use it. You tend to use a variable much more often than you declare it so the ugliness of a g prefix is an immediate and obvious reminder at the point of use that this is a global variable. Optimising for fewest key strokes only makes sense transmitting to Pluto or beyond	[reply]
Re^6: Pointers and References by LanX (Saint) on Nov 23, 2020 at 22:17 UTC
Re^7: Pointers and References by GrandFather (Saint) on Nov 23, 2020 at 22:29 UTC
Re^5: Pointers and References by jcb (Parson) on Nov 29, 2020 at 05:23 UTC
I use a simple convention: local variables have names in `all_lowercase`, global variables have names with an `Initial_capital`, and constants or quasi-constants have names that are `ALL_UPPERCASE`.	[reply]
Re^3: Pointers and References by Anonymous Monk on Nov 23, 2020 at 18:54 UTC
In this case, only the latter. He is doing it as a personal practice for designating the "main routine" of his program. do does have definite functional uses. None of them are being leveraged here.	[reply]