=== tests/cases/compiler/restParameterNoTypeAnnotation.ts ===
function foo(...rest) {   
>foo : (...rest: any[]) => number, Symbol(foo, Decl(restParameterNoTypeAnnotation.ts, 0, 0))
>rest : any[], Symbol(rest, Decl(restParameterNoTypeAnnotation.ts, 0, 13))

     var x: number = rest[0];
>x : number, Symbol(x, Decl(restParameterNoTypeAnnotation.ts, 1, 8))
>rest[0] : any
>rest : any[], Symbol(rest, Decl(restParameterNoTypeAnnotation.ts, 0, 13))
>0 : number

     return x;   
>x : number, Symbol(x, Decl(restParameterNoTypeAnnotation.ts, 1, 8))
}