How to fix 'noImplicitAny' is disabled in TypeScript

First, examine your tsconfig.json file for contradictory compiler options:

{
  "compilerOptions": {
    "strict": true,
    "noImplicitAny": false,  // ← This causes the warning!
    // ... other options
  }
}

The issue is that strict: true enables noImplicitAny (and other strict checks), but explicitly setting noImplicitAny: false overrides it. Remove the explicit noImplicitAny: false setting to resolve the conflict.

Choose one of these approaches:

Option A: Enable full strict mode (Recommended)

{
  "compilerOptions": {
    "strict": true,
    // Remove explicit noImplicitAny setting
  }
}

Option B: Disable strict mode and configure individually

{
  "compilerOptions": {
    "strict": false,
    "noImplicitAny": false,
    // Explicitly enable other strict checks you want
    "strictNullChecks": true,
    "strictFunctionTypes": true
  }
}

Option C: Use strict mode but disable specific checks

{
  "compilerOptions": {
    "strict": true,
    "noImplicitAny": false  // Only disable this specific check
  }
}

Option A is recommended for new projects. Option C is acceptable if you need to disable only noImplicitAny while keeping other strict checks.

In monorepo setups (like Nx, Lerna, or Yarn workspaces), check for tsconfig inheritance conflicts:

1. Root tsconfig.json (base configuration):

{
  "compilerOptions": {
    "strict": true
  }
}

2. Project tsconfig.json (should not contradict):

{
  "extends": "../../tsconfig.json",
  "compilerOptions": {
    // DO NOT set noImplicitAny: false here
    // Add project-specific options only
    "outDir": "./dist"
  }
}

If you need different settings per project, consider creating separate base configurations rather than overriding individual strict mode options.

If you choose to enable noImplicitAny, you'll need to fix implicit "any" types in your code:

Before:

function processData(data) {  // Error: Parameter 'data' implicitly has 'any' type
  return data.map(item => item.value);
}

After:

interface DataItem {
  value: string;
}

function processData(data: DataItem[]) {  // Explicit type annotation
  return data.map(item => item.value);
}

// Or use type inference with default values:
function processData(data: any[]) {  // Explicit 'any' if needed
  return data.map(item => item.value);
}

Use these patterns:
- Add explicit parameter and variable type annotations
- Define interfaces for complex data structures
- Use any explicitly when type is truly unknown (but consider unknown instead)
- Leverage TypeScript's type inference where possible

After making changes, verify the warning is resolved:

1. Run TypeScript compiler:

npx tsc --noEmit

2. Check for remaining warnings:

npx tsc --noEmit --listFiles

3. Test your build process:

npm run build
# or
yarn build

4. Check IDE integration: Restart your IDE (VS Code, WebStorm, etc.) to ensure it picks up the new configuration.

The "noImplicitAny is disabled" warning should no longer appear. You may see new type errors if you enabled noImplicitAny - these are legitimate issues to fix for better type safety.