Mustachio: avoid calling Iterable getter multiple times #2546
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Take this template, where `widgets` is an Iterable property:
Text {{#widgets}} {{name}} {{/widgets}}.
A mustache renderer should assume that the `widgets` getter may have side
effects, and it should only be called one time. Currently, Mustachio will call
this getter 2 or 3 times, as the behavior differs if the section is inverted,
and if the Iterable is empty.
This change is actually quite readable, and simplifies the code. The magic
sauce is in the lazy Iterable returned by `renderIterable`. If Mustachio does
not wish to render the elements, then the lazy map will not be evaluated.
parlough
reviewed
Feb 25, 2021
parlough
approved these changes
Feb 26, 2021
|
@srawlins Can you merge master into your PRs to get the tests passing? |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
Take this template, where
widgetsis an Iterable property:A mustache renderer should assume that the
widgetsgetter may have sideeffects and may be expensive to compute, and it should only be called one
time. Currently, Mustachio will call this getter 2 or 3 times, as the behavior
differs if the section is inverted, and if the Iterable is empty.
This change is actually quite readable, and simplifies the code. The magic
sauce is in the lazy Iterable returned by
renderIterable. If Mustachio doesnot wish to render the elements, then the lazy map will not be evaluated.