/index.ts(1,12): error TS7006: Parameter 'x' implicitly has an 'any' type.
/index.ts(3,1): error TS2454: Variable 'y' is used before being assigned.


==== /tsconfig.json (0 errors) ====
    {
        "extends": ["./tsconfig1.json", "./tsconfig2.json"]
    }
    
==== /tsconfig1.json (0 errors) ====
    {
        "compilerOptions": {
            "strictNullChecks": true
        }
    }
    
==== /tsconfig2.json (0 errors) ====
    {
        "compilerOptions": {
            "noImplicitAny": true
        }
    }
    
==== /index.ts (2 errors) ====
    function f(x) { } // noImplicitAny error
               ~
!!! error TS7006: Parameter 'x' implicitly has an 'any' type.
    let y: string;
    y.toLowerCase(); // strictNullChecks error
    ~
!!! error TS2454: Variable 'y' is used before being assigned.