Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Base sequences, dictionaries, and records on Infra types #317

Merged
merged 3 commits into from
Feb 22, 2017
Merged

Base sequences, dictionaries, and records on Infra types #317

Changes from all commits
Commits
Show all changes
3 commits
Select commit Hold shift + click to select a range
6f4d405
Base sequences, dictionaries, and records on Infra types
domenic Feb 22, 2017
a1a038d
Address jyasskin's feedback.
domenic Feb 22, 2017
287684d
Fix extra word per tobie
domenic Feb 22, 2017
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
66 changes: 40 additions & 26 deletions index.bs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -27,6 +27,10 @@ Abstract: are interoperable.
Boilerplate: omit issues-index, omit conformance, omit feedback-header
</pre>

<pre class="link-defaults">
spec: infra; type: dfn; text: list
</pre>

<pre class="anchors">
urlPrefix: https://html.spec.whatwg.org/; spec: HTML
type: interface
Expand Down Expand Up @@ -132,7 +136,6 @@ urlPrefix: https://tc39.github.io/ecma262/; spec: ECMA-262
text: ECMA-262 section 9.1.8; url: sec-ordinary-object-internal-methods-and-internal-slots-get-p-receiver
text: ECMA-262 section 19.2.2.3; url: sec-function-@@create
text: ECMA-262 section 19.2.3.8; url: sec-function.prototype-@@hasinstance
text: List; url: sec-list-and-record-specification-type
text: Array methods; url: sec-properties-of-the-array-prototype-object
text: typed arrays; url: sec-typedarray-objects
text: GetMethod; url: sec-getmethod
Expand Down Expand Up @@ -4050,9 +4053,9 @@ namespaces.

A <dfn id="dfn-dictionary" export>dictionary</dfn> is a definition (matching
<emu-nt><a href="#prod-Dictionary">Dictionary</a></emu-nt>)
used to define an associative array data type with a fixed, ordered set of key–value pairs,
used to define an [=ordered map=] data type with a fixed, ordered set of [=map/entries=],
termed <dfn id="dfn-dictionary-member" export>dictionary members</dfn>,
where keys are strings and values are of a particular type specified in the definition.
where [=map/keys=] are strings and [=map/values=] are of a particular type specified in the definition.

<pre highlight="webidl" class="syntax">
dictionary identifier {
Expand Down Expand Up @@ -4104,6 +4107,11 @@ the value to use for the dictionary member when passing a value to a
not have a specified value. Dictionary members with default values are
always considered to be present.

An [=ordered map=] with string [=map/keys=] can be implicitly treated as a dictionary value of a
specific dictionary |D| if all of its [=map/entries=] correspond to [=dictionary members=], in the
correct order and with the correct types, and with appropriate [=map/entries=] for any required
dictionary members.

<p class="advisement">
As with [=optional argument/default value|operation argument default values=],
is strongly suggested not to use of <emu-val>true</emu-val> as the
Expand Down Expand Up @@ -5662,7 +5670,10 @@ identifies a [=dictionary=] is used to refer to
a type that corresponds to the set of all dictionaries that adhere to
the dictionary definition.

There is no way to represent a constant dictionary value in IDL.
The literal syntax for [=ordered maps=] may also be used to represent dictionaries, when it is
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

\o/

implicitly understood from context that the map is being treated as an instance of a specific
dictionary type. However, there is no way to represent a constant dictionary value inside IDL
fragments.

The [=type name=] of a dictionary type
is the [=identifier=] of the dictionary.
Expand Down Expand Up @@ -5765,7 +5776,7 @@ the string “OrNull”.
<h4 oldids="dom-sequence" id="idl-sequence" lt="sequence" dfn export>Sequence types — sequence&lt;|T|&gt;</h4>

The <dfn lt="sequence type" export>sequence&lt;|T|&gt;</dfn>
type is a parameterized type whose values are (possibly zero-length) sequences of
type is a parameterized type whose values are (possibly zero-length) [=lists=] of
values of type |T|.

Sequences are always passed by value. In
Expand All @@ -5775,7 +5786,9 @@ will not result in a reference to the sequence being kept by that object.
Similarly, any sequence returned from a platform object
will be a copy and modifications made to it will not be visible to the platform object.

There is no way to represent a constant sequence value in IDL.
The literal syntax for [=lists=] may also be used to represent sequences, when it is implicitly
understood from context that the list is being treated as a sequences. However, there is no way to
represent a constant sequence value inside IDL fragments.

Sequences must not be used as the
type of an [=attribute=] or
Expand All @@ -5792,22 +5805,19 @@ The [=type name=] of a sequence type
is the concatenation of the type name for |T| and
the string “Sequence”.

Any [=list=] can be implicitly treated as a <code>sequence&lt;|T|&gt;</code>, as long as it contains
only [=list/items=] that are of type |T|.

<h4 id="idl-record" lt="record" dfn export>Record types — record&lt;|K|, |V|&gt;</h4>

A <dfn export>record type</dfn> is a parameterized type
whose values are ordered associative arrays mapping instances of |K| to
instances of |V|. The (key, value) pairs are called
<dfn for=record export>mappings</dfn>.
The order of a record's mappings is determined when the record value is created.
In a specification, a record's value can be written:
<blockquote>
« (key1, value1), (key2, value2), … »
</blockquote>
<h4 id="idl-record" lt="record" dfn export>Record types — record&lt;|K|, |V|&gt;</h4>

However, there is no way to represent a constant record value in IDL.
A <dfn export>record type</dfn> is a parameterized type whose values are [=ordered maps=] with
[=map/keys=] that are instances of |K| and [=map/values=] that are instances of |V|. |K| must be one
of {{DOMString}}, {{USVString}}, or {{ByteString}}.

|K| must be one of {{DOMString}}, {{USVString}}, or {{ByteString}}.
The literal syntax for [=ordered maps=] may also be used to represent records, when it is implicitly
understood from context that the map is being treated as a record. However, there is no way to
represent a constant record value inside IDL fragments.

Records are always passed by value. In language bindings where a record
is represented by an object of some kind, passing a record
Expand All @@ -5822,6 +5832,10 @@ Records must not be used as the type of an [=attribute=] or
The [=type name=] of a record type is the concatenation of the type
name for |K|, the type name for |V| and the string “Record”.

Any [=ordered map=] can be implicitly treated as a <code>record&lt;|K|, |V|&gt;</code>, as long as
it contains only [=map/entries=] whose [=map/keys=] are all of of type |K| and whose [=map/values=]
are all of type |V|.


<h4 oldids="dom-promise" id="idl-promise" interface lt="Promise|Promise&lt;T&gt;">Promise types — Promise&lt;|T|&gt;</h4>

Expand Down Expand Up @@ -7415,17 +7429,17 @@ ECMAScript <emu-val>Object</emu-val> values.
[=ECMAScript/throw=] a <emu-val>TypeError</emu-val>.
1. Let |result| be a new empty instance of <code>[=record=]&lt;|K|, |V|></code>.
1. Let |keys| be [=?=] |O|.\[[OwnPropertyKeys]]().
1. Repeat, for each element |key| of |keys| in [=List=] order:
1. [=list/For each=] |key| of |keys|:
1. Let |desc| be [=?=] |O|.\[[GetOwnProperty]](|key|).
1. If |desc| is not <emu-val>undefined</emu-val>
and |desc|.\[[Enumerable]] is <emu-val>true</emu-val>:
1. Let |typedKey| be |key| [=converted to an IDL value=] of type |K|.
1. Let |value| be [=?=] [=Get=](|O|, |key|).
1. Let |typedValue| be |value| [=converted to an IDL value=] of type |V|.
1. If |typedKey| is already a key in |result|, set its value to |typedValue|.
1. [=map/Set=] |result|[|typedKey|] to |typedValue|.

Note: This can happen when |O| is a proxy object.
1. Otherwise, append to |result| a [=record/mapping=] (|typedKey|, |typedValue|).
Note: it's possible that |typedKey| is already in |result|, if |O| is a proxy
object.
1. Return |result|.
</div>

Expand All @@ -7436,7 +7450,7 @@ ECMAScript <emu-val>Object</emu-val> values.
to an ECMAScript value as follows:

1. Let |result| be [=!=] [=ObjectCreate=]([=%ObjectPrototype%=]).
1. Repeat, for each [=record/mapping=] (|key|, |value|) in |D|:
1. [=map/For each=] |key| → |value| of |D|:
1. Let |esKey| be |key| [=converted to an ECMAScript value=].
1. Let |esValue| be |value| [=converted to an ECMAScript value=].
1. Let |created| be [=!=] [=CreateDataProperty=](|result|, |esKey|, |esValue|).
Expand All @@ -7448,7 +7462,7 @@ ECMAScript <emu-val>Object</emu-val> values.

Passing the ECMAScript value <code>{b: 3, a: 4}</code> as a
<code>[=record=]&lt;DOMString, double></code> argument
would result in the IDL value « ("b", 3), ("a", 4) ».
would result in the IDL value «[ "b" → 3, "a" → 4 ]».

Records only consider [=own property|own=] [=enumerable=]
properties, so given an IDL operation
Expand Down Expand Up @@ -7484,12 +7498,12 @@ ECMAScript <emu-val>Object</emu-val> values.
<tr>
<td><code>{"\uD83D": 1}</code></td>
<td><code>[=record=]&lt;USVString, double></code></td>
<td>« ("\uFFFD", 1) »</td>
<td>«[ "\uFFFD" → 1 ]»</td>
</tr>
<tr>
<td><code>{"\uD83D": {hello: "world"}}</code></td>
<td><code>[=record=]&lt;DOMString, double></code></td>
<td>« ("\uD83D", 0) »</td>
<td>«[ "\uD83D" → 0 ]»</td>
</tr>
</table>
</div>
Expand Down