78 lines
2.8 KiB
TypeScript
78 lines
2.8 KiB
TypeScript
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/**
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* @license
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* Copyright Google Inc. All Rights Reserved.
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*
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* Use of this source code is governed by an MIT-style license that can be
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* found in the LICENSE file at https://angular.io/license
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*/
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import {_global} from './src/global';
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import {$localize as _localize, LocalizeFn, TranslateFn} from './src/localize';
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// Attach $localize to the global context, as a side-effect of this module.
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_global.$localize = _localize;
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export {LocalizeFn, TranslateFn};
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// `declare global` allows us to escape the current module and place types on the global namespace
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declare global {
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/**
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* Tag a template literal string for localization.
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*
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* For example:
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*
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* ```ts
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* $localize `some string to localize`
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* ```
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*
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* **Naming placeholders**
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*
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* If the template literal string contains expressions then you can optionally name the
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* placeholder
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* associated with each expression. Do this by providing the placeholder name wrapped in `:`
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* characters directly after the expression. These placeholder names are stripped out of the
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* rendered localized string.
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*
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* For example, to name the `item.length` expression placeholder `itemCount` you write:
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*
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* ```ts
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* $localize `There are ${item.length}:itemCount: items`;
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* ```
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*
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* If you need to use a `:` character directly an expression you must either provide a name or you
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* can escape the `:` by preceding it with a backslash:
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*
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* For example:
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*
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* ```ts
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* $localize `${label}:label:: ${}`
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* // or
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* $localize `${label}\: ${}`
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* ```
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*
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* **Processing localized strings:**
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*
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* There are three scenarios:
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*
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* * **compile-time inlining**: the `$localize` tag is transformed at compile time by a
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* transpiler,
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* removing the tag and replacing the template literal string with a translated literal string
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* from a collection of translations provided to the transpilation tool.
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*
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* * **run-time evaluation**: the `$localize` tag is a run-time function that replaces and
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* reorders
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* the parts (static strings and expressions) of the template literal string with strings from a
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* collection of translations loaded at run-time.
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*
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* * **pass-through evaluation**: the `$localize` tag is a run-time function that simply evaluates
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* the original template literal string without applying any translations to the parts. This
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* version
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* is used during development or where there is no need to translate the localized template
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* literals.
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*
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* @param messageParts a collection of the static parts of the template string.
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* @param expressions a collection of the values of each placeholder in the template string.
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* @returns the translated string, with the `messageParts` and `expressions` interleaved together.
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*/
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const $localize: LocalizeFn;
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}
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