Linter rule
A linter rule is a configurable condition applied by a linter to detect or enforce specified patterns or constraints in code or other artifacts.
Automating API Delivery
A custom linting rule is a user-defined validation rule that specifies where and how an API definition is checked.
- How it is used
- Checks static API definitions against executable API style-guide guidelines during design and CI/CD.
- How deep it goes
- Works through Spectral selectors, validation functions, severity, CLI testing, and custom-function escalation; leaves semantic judgment beyond simple rules.
- Examples
- Uses a missing `info.description`, versioned URI paths, and GET `operationId` naming conventions as rule targets.
- What you can do after
- Build it from scratch with Spectral selectors and functions, test violations, and apply organizational severity and pipeline policy.
"Looks Good to Me"
A linting rule is a configured criterion that a linter applies to source code to detect a particular pattern or violation.
- How it is used
- Uses configured checks to automate team style and catch code concerns before review.
- How deep it goes
- Defines rule scope, granularity, and severity with practical configurations, but does not explain linter internals.
- Examples
- Uses Stroustrup braces, no-var, duplicate-import, equality, console, and unnecessary-ternary checks as concrete examples.
- What you can do after
- Apply it via ESLint to enforce selected checks, tune warning or error severity, and reduce recurring review issues.
Terraform in Depth: Infrastructure as Code with Terraform and OpenTofu
A linter rule is a configurable static-analysis check that specifies a condition source or configuration must satisfy.
- How it is used
- Applies static checks to Terraform configuration during quality and continuous-integration workflows.
- How deep it goes
- Explains rule selection, plugin configuration, diagnostics, disabling, and inline exceptions, but not rule implementation internals.
- Examples
- Uses Terraform plugin presets, required_version and unused-provider diagnostics, cloud plugins, Makefile commands, and inline ignore comments.
- What you can do after
- Operate TFLint by enabling plugins, selecting presets, interpreting findings, customizing rules, and recording narrow exceptions.
Essential TypeScript 5, Third Edition
A linting rule is a configurable condition that determines whether a linter reports a particular source-code pattern or violation.
- How it is used
- Configures lint feedback so warnings remain relevant to project-wide standards and temporary debugging needs.
- How deep it goes
- Explains numeric configuration values and statement-level suppression, but does not detail rule implementation internals.
- Examples
- Uses prefer-const in .eslintrc and no-debugger with an eslint-disable-line comment.
- What you can do after
- Operate ESLint by enabling or disabling rules globally and suppressing selected violations on individual statements.
Read how Essential TypeScript 5, Third Edition explains linter rule →
Related concepts
- ESLintused by · ESLint is an open-source, configurable static-analysis tool that identifies and optionally fixes coding problems in JavaScript, TypeScript, and related source code.
- JSON path languageuses · JSONPath is a query language and expression syntax for navigating, selecting, and extracting values from hierarchical JSON documents.
- rulesetpart of · A ruleset is an organized collection of rules applied together to evaluate inputs, guide decisions, or govern behavior.
- guidelineuses · A guideline is a recommendation or principle that directs how an activity is performed or decisions are made, without necessarily imposing an absolute requirement.
- configurationconfigured by · A specification of settings, parameters, or component relationships that determines how a system, application, model, or process is structured or operates.
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