concatError.ts(10,6): error TS2454: Variable 'fa' is used before being assigned.


==== concatError.ts (1 errors) ====
    var n1: number[];
    /*
    interface Array<T> {
        concat(...items: T[][]): T[]; // Note: This overload needs to be picked for arrays of arrays, even though both are applicable
        concat(...items: T[]): T[];
    }
    */
    var fa: number[];
    
    fa = fa.concat([0]);
         ~~
!!! error TS2454: Variable 'fa' is used before being assigned.
    fa = fa.concat(0);
    
    
    
    
    
    /*
    
    
    
    
    declare class C<T> {
    	public m(p1: C<C<T>>): C<T>;
    	//public p: T;
    }
    
    var c: C<number>;
    var cc: C<C<number>>;
    
    c = c.m(cc);
    */