After the introduction of the view engine, we can drop a lot of code that is not used any more.
This should reduce the size of the app bundles because a lot of this code was not being properly tree-shaken by today's tools even though it was dead code.
When the `enableLegacyTemplate` is set to `false`, `<template>` tags and the
`template` attribute are no more used to define angular templates but are
treated as regular tag and attribute.
The default value is `true`.
In order to define a template, you have to use the `<ng-template>` tag.
This option applies to your application and all the libraries it uses. That is
you should make sure none of them rely on the legacy way to defined templates
when this option is turned off (`false`).
The rationale of this change is to improve the inter-operability with web
components that might make use of the `<template>` tag.
DEPRECATION
The template tags and template attribute are deprecated:
<template ngFor [ngFor]=items let-item><li>...</li></template>
<li template="ngFor: let item of items">...</li>
should be rewritten as:
<ng-template ngFor [ngFor]=items let-item><li>...</li></ng-template>
Note that they still be supported in 4.x with a deprecartion warning in
development mode.
MIGRATION
- `template` tags (or elements with a `template` attribute) should be rewritten
as a `ng-template` tag,
- `ng-content` selectors should be updated to referto a `ng-template` where they
use to refer to a template: `<ng-content selector="template[attr]">` should be
rewritten as `<ng-content selector="ng-template[attr]">`
- if you consume a component relying on your templates being actual `template`
elements (that is they include a `<ng-content selector="template[attr]">`). You
should still migrate to `ng-template` and make use of `ngProjectAs` to override
the way `ng-content` sees the template:
`<ng-template projectAs="template[attr]">`
- while `template` elements are deprecated in 4.x they continue to work.
Aspects: di, query, content projection
Included refactoring:
- use a number as query id
- use a bloom filter for aggregating matched queries of nested elements
- separate static vs dynamic queries
Part of #14013
Included refactoring:
- make ViewData.parentIndex point to component provider index
- split NodeType.Provider into Provider / Directive / Pipe
- make purePipe take the real pipe as argument to detect changes
- order change detection:
1) directive props
2) renderer props
Part of #14013
PR Close#14412
Subclassing errors is problematic since Error returns a
new instance. All of the patching which we do than prevent
proper application of source maps.
PR Close#14160
There are restrictions on the character set that can be used for xmb and xtb
placeholder names.
However because changing the placeholder names would change the message IDs it
is not possible to add those restrictions to the names used internally. Then we
have to map internal name to public names when generating an xmb file and back
when translating using an xtb file.
Note for implementors of `Serializer`:
- When writing a file, the implementor should take care of converting the
internal names to public names while visiting the message nodes - this is
required because the original nodes are needed to compute the message ID.
- When reading a file, the implementor does not need to take care of the mapping
back to internal names as this is handled in the `I18nToHtmlVisitor` used by the
`TranslationBundle`.
fixes b/34339636
Fixes:
- Inject the i18n specific HtmlParser into the directive normalizer,
- Parse ICU messages while normalizing templates,
- Normalize (visit) the content of ICU messages.
🎄🎁🎅
Chuck Jazdzewski
vikerman
Tobias Bosch
Marc Laval
Victor Berchet
Miško Hevery
Dzmitry Shylovich
Bowen Ni
Alex Eagle
Gion Kunz
Dzmitry Shylovich