Re^4: On Backwards Compatibility and Bareword Filehandles

That is a short summary of the impression that I got from previous discussions on the topic of indirect filehandles in Perl, particularly in the case of code at the top-level of the main script, where a (global) bareword filehandle and a file-scope lexical have effectively the same scope.

There seems to be some confusion here — I am arguing that bareword filehandles should remain in the language, but suggesting a compromise of making bareword filehandles lexical variables. I expect that the arguments in favor of declaring bareword filehandles (and giving them lexical scope) are essentially the rationale for use strict 'subs' prohibiting the old "bareword-as-unquoted-string" behavior.

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Re^5: On Backwards Compatibility and Bareword Filehandles by ikegami (Patriarch) on Jul 19, 2020 at 11:50 UTC
where a (global) bareword filehandle and a file-scope lexical have effectively the same scope. Globs (which you call bareword file handle) and other package variables are global, which means visible everywhere. File-scoped lexicals are still lexically-scoped. They aren't seen outside the file.	[reply]
Re^6: On Backwards Compatibility and Bareword Filehandles by jcb (Parson) on Jul 20, 2020 at 00:35 UTC
package variables are global, which means visible everywhere. Close — fully-qualified names are visible everywhere, but most "global" variables are implicitly scoped to the current package. File-scoped lexicals are still lexically-scoped. They aren't seen outside the file. If a 1:1 correspondence between files and packages (as is convention) is maintained, those are equivalent, with the exception that you can refer to a package "global" variable from elsewhere if you specifically do so. In terms of "accidents", the risks for a package variable and file-scope lexical are very similar.	[reply]
Re^7: On Backwards Compatibility and Bareword Filehandles (Orthogonality) by LanX (Saint) on Jul 20, 2020 at 01:24 UTC
I spend much time training colleagues in Perl. I'm pretty happy when they understood scoping rules and follow the basics of declaring with `my`. And believe me, nobody there thought much about using `package` before I started there. There is simply not much room to tell a beginner about all the specialties of a package scoped bareword, which needs to be treated with local, the internals of type-globs and how to pass them around as reference with `\*FH` . Yes Perl has many ways to do it and it's impressive how I can always come up with a nifty trick to fix the sins of a 15 year old code base. But orthogonality rules, they don't need to learn how to use a baseball bat to drive a nail into the wall, if there is a hammer called `my $FH` and they already learned to use that hammer with many other nails ... And there is no issue with "backwards compatibility" whatsoever! Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply] [d/l] [select]
Re^8: On Backwards Compatibility and Bareword Filehandles by jcb (Parson) on Jul 20, 2020 at 02:10 UTC
Re^9: On Backwards Compatibility and Bareword Filehandles by LanX (Saint) on Jul 20, 2020 at 02:29 UTC
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Re^7: On Backwards Compatibility and Bareword Filehandles by ikegami (Patriarch) on Jul 21, 2020 at 02:39 UTC
In terms of "accidents", the risks for a package variable and file-scope lexical are very similar. I didn't say otherwise. The fact that they have similar risks doesn't make them the same thing.	[reply]