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Moderne licensed

Find s = s + "..." string concatenation inside loops

Recipe IDorg.openrewrite.kotlin.performance.FindStringPlusInLoop$KtRecipe
Artifactio.moderne.recipe:recipes-kotlin

Repeated String concatenation inside a loop allocates a new String on every iteration — each + produces a fresh StringBuilder. Prefer building once with StringBuilder (or buildString { … }).

Single recipeProprietary

Usage

This recipe has no required configuration options. You’ll need the Moderne CLI configured before running the command below.

mod run . --recipe org.openrewrite.kotlin.performance.FindStringPlusInLoop$KtRecipe

If the recipe isn’t available locally, install it with:

mod config recipes jar install io.moderne.recipe:recipes-kotlin:0.2.0

Data tables

Structured output this recipe can produce.

  • Source files that had resultsSource files that were modified by the recipe run.org.openrewrite.table.SourcesFileResults
  • Source files that had search resultsSearch results that were found during the recipe run.org.openrewrite.table.SearchResults
  • Source files that errored on a recipeThe details of all errors produced by a recipe run.org.openrewrite.table.SourcesFileErrors
  • Recipe performanceStatistics used in analyzing the performance of recipes.org.openrewrite.table.RecipeRunStats