Re: $a.foo() moved?
HaloO, Larry Wall wrote: Sure, that one might be obvious, but quick, tell me what these mean: say .bar say .() say .1 when .bar when .() when .1 foo .bar foo .() foo .1 .foo .bar .foo .() .foo .1 I'd rather have a rule you don't have to think about so hard. To me that implies something simple that let's you put whitespace *into* a postfix without violating the postfixes don't take preceding whitespace rule. To me your examples fall into three categories that are distinguished by the type of characters following the dot .bar # identifier -- postfix method .() # parens -- postfix invocation .1# number literal From there on the difficulty comes not from the syntax but the intended semantics! E.g. the non-whitespace when(), when.() and when.bar are syntax errors, right? So why should the whitespace version suddenly mean invocation or dispatch on topic? The only thing that bothers me is that more parens and explicit $_ will be needed. E.g. say (.bar) or say $_.bar in the first triple. And the compiler has to know something about the bare foo. Apart from that the syntactic rules are simple. --
$a.foo() moved?
All~ I just noticed something claiming that C$a. foo() is actually C$a.foo() (a method call on C$a) and that C$a .foo() is actually C$a $_.foo() (likely a syntax error). When did this change? Why did this change? Also, I liked it better when C$a .foo() was a method call on C$a. Thanks, Matt -- Computer Science is merely the post-Turing Decline of Formal Systems Theory. -Stan Kelly-Bootle, The Devil's DP Dictionary
Re: $a.foo() moved?
On Thu, Apr 06, 2006 at 01:58:55PM -0400, Matt Fowles wrote: : All~ : : I just noticed something claiming that C$a. foo() is actually : C$a.foo() (a method call on C$a) and that C$a .foo() is actually : C$a $_.foo() (likely a syntax error). : : When did this change? Why did this change? It changed at the last hackathon, but is still being debated, mostly on #perl6. The current S02 early dot rule is likely being abandoned, but we don't know for what yet. The reason is that term/operator lexer state is interacting badly with inconsistent retroactive whitespace cancellation. : Also, I liked it better when C$a .foo() was a method call on C$a. Sure, that one might be obvious, but quick, tell me what these mean: say .bar say .() say .1 when .bar when .() when .1 foo .bar foo .() foo .1 .foo .bar .foo .() .foo .1 I'd rather have a rule you don't have to think about so hard. To me that implies something simple that let's you put whitespace *into* a postfix without violating the postfixes don't take preceding whitespace rule. Larry
Re: $a.foo() moved?
Larry~ On 4/6/06, Larry Wall [EMAIL PROTECTED] wrote: On Thu, Apr 06, 2006 at 01:58:55PM -0400, Matt Fowles wrote: : All~ : : I just noticed something claiming that C$a. foo() is actually : C$a.foo() (a method call on C$a) and that C$a .foo() is actually : C$a $_.foo() (likely a syntax error). : : When did this change? Why did this change? It changed at the last hackathon, but is still being debated, mostly on #perl6. The current S02 early dot rule is likely being abandoned, but we don't know for what yet. The reason is that term/operator lexer state is interacting badly with inconsistent retroactive whitespace cancellation. : Also, I liked it better when C$a .foo() was a method call on C$a. Sure, that one might be obvious, but quick, tell me what these mean: say .bar say .() say .1 when .bar when .() when .1 foo .bar foo .() foo .1 .foo .bar .foo .() .foo .1 I'd rather have a rule you don't have to think about so hard. To me that implies something simple that let's you put whitespace *into* a postfix without violating the postfixes don't take preceding whitespace rule. That makes a good deal of sense. I don't know what I would like more, so I guess that I will wait till a more firm consensus is reached. Matt -- Computer Science is merely the post-Turing Decline of Formal Systems Theory. -Stan Kelly-Bootle, The Devil's DP Dictionary
Re: $a.foo() moved?
On Thu, Apr 06, 2006 at 02:35:53PM -0400, Matt Fowles wrote: : That makes a good deal of sense. I don't know what I would like more, : so I guess that I will wait till a more firm consensus is reached. The current consensus on #perl6 is that, in postfix position only (that is, with no leading whitespace), m:p/\.+ \sws before \./ lets you embed arbitrary whitespace, comments, pod, etc, within the postfix operator. This allows both the short :foo. .() as well as the longer $x... .foo() Or possibly m:p/ [ \.+ \sws ]+before \./, which would let you intermix as many dots into the whitespace as you like: $x. . . . . .() But that's a little out there. In any event $x..$y is still a range because there's no whitespace after .. and $x .. $y is still a range *because* there's whitespace before. The only casualty is $x... with trailing whitespace can't mean $x..Inf. But you almost always want to put something like a comma or bracket after it anyway. And the nice thing is that it becomes a drop-dead simple rule that postfix operators never, ever have leading whitespace, and you can always distingish an infix operator from a postfix by whitespace. No more retroactive guessing games. It's possible the $x... infinite range operator could be recast to something else like $x..* or some such, but that's a niggle compared to the enormity of cleaner parsing. Larry
Re: $a.foo() moved?
On Thu, Apr 06, 2006 at 12:10:18PM -0700, Larry Wall wrote: The current consensus on #perl6 is that, in postfix position only (that is, with no leading whitespace), m:p/\.+ \sws before \./ lets you embed arbitrary whitespace, comments, pod, etc, within the postfix operator. This allows both the short :foo. .() as well as the longer $x... .foo() The one quibble I see with this is that postfix one or more dots, including 3 might be a touch confusing with infixexactly 3 dots (i.e. the yada operator). Depending upon context ... can thus be either an error (code not yet written) or layout control and valid to execute (I put execute in quotes because by the time you get around to executing the code the ... will have served it purpose of controlling the parsing and be gone). (This is just the one-shot I'm not used to it yet vote. :-) --
Re: $a.foo() moved?
On Thu, Apr 06, 2006 at 03:38:59PM -0400, John Macdonald wrote: On Thu, Apr 06, 2006 at 12:10:18PM -0700, Larry Wall wrote: The current consensus on #perl6 is that, in postfix position only (that is, with no leading whitespace), m:p/\.+ \sws before \./ lets you embed arbitrary whitespace, comments, pod, etc, within the postfix operator. The one quibble I see with this is that postfix one or more dots, including 3 might be a touch confusing with infixexactly 3 dots (i.e. the yada operator). There isn't an infix:... operator. There's term:... (yada yada yada), and there's postfix:... ($x..Inf). Pm
Re: $a.foo() moved?
On Thu, Apr 06, 2006 at 02:49:33PM -0500, Patrick R. Michaud wrote: On Thu, Apr 06, 2006 at 03:38:59PM -0400, John Macdonald wrote: On Thu, Apr 06, 2006 at 12:10:18PM -0700, Larry Wall wrote: The current consensus on #perl6 is that, in postfix position only (that is, with no leading whitespace), m:p/\.+ \sws before \./ lets you embed arbitrary whitespace, comments, pod, etc, within the postfix operator. The one quibble I see with this is that postfix one or more dots, including 3 might be a touch confusing with infixexactly 3 dots (i.e. the yada operator). There isn't an infix:... operator. There's term:... (yada yada yada), and there's postfix:... ($x..Inf). Hmm, yep I got the terminology wrong, but my point remains - one operator that is ..., exactly 3 dots, and another that can be ... but can be spelled with a different number of dots if you feel like it, is somewhat confusing. --
