Use Dictionary.TryAdd instead of ContainsKey and indexer by reducing lookups. #917
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Pull request overview
This PR improves performance by replacing the ContainsKey + indexer pattern with the more efficient Dictionary.TryAdd method, which reduces dictionary lookups from two operations to one. A polyfill implementation is provided for older frameworks that don't have native TryAdd support.
Key Changes:
- Added a polyfill
DictionaryExtensions.TryAddfor frameworks prior to .NET Standard 2.1 - Replaced
ContainsKey+ indexer pattern withTryAddin three locations - Reduced dictionary lookup operations for better performance
Reviewed changes
Copilot reviewed 4 out of 4 changed files in this pull request and generated 1 comment.
| File | Description |
|---|---|
| src/Markdig/Polyfills/DictionaryExtensions.cs | Adds TryAdd polyfill for older .NET frameworks |
| src/Markdig/Syntax/LinkReferenceDefinitionGroup.cs | Uses TryAdd in Set method to reduce lookups |
| src/Markdig/Parsers/ParserList.cs | Uses TryAdd when counting opening characters |
| src/Markdig/Helpers/CharacterMap.cs | Uses TryAdd when building non-ASCII character map |
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Co-authored-by: Copilot <[email protected]>
gfoidl
reviewed
Nov 29, 2025
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This PR replace Dictionary.TryAdd instead of ContainsKey and indexer by reducing lookups.