Add enum for user-definable operators.

Add enum for user-definable operators.

R=lrn@google.com

Committed: https://github.com/dart-lang/sdk/commit/91bea04dcb537cfddd137ccbcf5b4988de0b74ab

[ahe, 2017-02-08 11:49:22]

ahe@google.com changed reviewers:
+ lrn@google.com

[ahe, 2017-02-08 11:49:23]

https://codereview.chromium.org/2684933002/diff/1/pkg/front_end/lib/src/fasta...
File pkg/front_end/lib/src/fasta/operator.dart (right):

https://codereview.chromium.org/2684933002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/operator.dart:12: BitwiseAnd,
Note: I'm using "bitwise" prefix here because I think it's clearer when used in
other places in the compiler. This is regardless that, for example, "And", would
be unique in this enum without the prefix.

[Lasse Reichstein Nielsen, 2017-02-08 13:15:46]

lgtm

https://codereview.chromium.org/2684933002/diff/1/pkg/front_end/lib/src/fasta...
File pkg/front_end/lib/src/fasta/operator.dart (right):

https://codereview.chromium.org/2684933002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/operator.dart:11: Add,
Using UpperCamelCase is usually reserved for types.

Style guide recommends lowerCamelCase names for constants, allows SCREAMING_CAPS
for backwards compatability.

https://codereview.chromium.org/2684933002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/operator.dart:12: BitwiseAnd,
On 2017/02/08 11:49:22, ahe wrote:
> Note: I'm using "bitwise" prefix here because I think it's clearer when used
in
> other places in the compiler. This is regardless that, for example, "And",
would
> be unique in this enum without the prefix.

Acknowledged.

https://codereview.chromium.org/2684933002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/operator.dart:26: Percent,
Should be Modulo

https://codereview.chromium.org/2684933002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/operator.dart:53: if (identical("unary-", string))
return Operator.UnaryMinus;
Would a hash-map possibly be more efficient than linear search?

Probably not a library one, but a custom perfect-hash based one, since you have
a fixed number of known strings. Otherwise the overhead quickly eats doing the
repeated identical tests.

[ahe, 2017-02-08 14:03:37]

Thank you, Lasse!

https://codereview.chromium.org/2684933002/diff/1/pkg/front_end/lib/src/fasta...
File pkg/front_end/lib/src/fasta/operator.dart (right):

https://codereview.chromium.org/2684933002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/operator.dart:11: Add,
On 2017/02/08 13:15:45, Lasse Reichstein Nielsen wrote:
> Using UpperCamelCase is usually reserved for types.
> 
> Style guide recommends lowerCamelCase names for constants, allows
SCREAMING_CAPS
> for backwards compatability. 

I've been using CamelCase to avoid conflicts with keywords, for example, see
modifier.dart in this directory.

There are no conflicts here, so I'll change to camelCase.

Since we're discussing this, what are your thoughts on modifier.dart?

https://codereview.chromium.org/2684933002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/operator.dart:26: Percent,
On 2017/02/08 13:15:46, Lasse Reichstein Nielsen wrote:
> Should be Modulo

Done.

https://codereview.chromium.org/2684933002/diff/1/pkg/front_end/lib/src/fasta...
pkg/front_end/lib/src/fasta/operator.dart:53: if (identical("unary-", string))
return Operator.UnaryMinus;
On 2017/02/08 13:15:45, Lasse Reichstein Nielsen wrote:
> Would a hash-map possibly be more efficient than linear search?
> 
> Probably not a library one, but a custom perfect-hash based one, since you
have
> a fixed number of known strings. Otherwise the overhead quickly eats doing the
> repeated identical tests.
> 

I'm concerned about performance here as well. My thoughts have been to add this
information to the corresponding PrecedenceInfo object, see
pkg/front_end/lib/src/fasta/scanner/precedence.dart.

[ahe, 2017-02-08 14:04:11]

Description was changed from

==========
Add enum for user-definable operators.
==========

to

==========
Add enum for user-definable operators.

R=lrn@google.com

Committed:
https://github.com/dart-lang/sdk/commit/91bea04dcb537cfddd137ccbcf5b4988de0b74ab
==========

[ahe, 2017-02-08 14:04:13]

Committed patchset #2 (id:20001) manually as
91bea04dcb537cfddd137ccbcf5b4988de0b74ab (presubmit successful).

[ahe, 2017-02-08 14:31:25]

FWIW, it was easy to switch to lowercase using this feature of Emacs:
http://steve-yegge.blogspot.dk/2006/06/shiny-and-new-emacs-22.html#replace