Check out example codes for "typescript list concat". It will help you in understanding the concepts better.

Code Example 1

this.results = [ ...this.results, ...data.results];

Code Example 2

var alpha = ["a", "b", "c"]; 
var numeric = [1, 2, 3];

var alphaNumeric = alpha.concat(numeric); 
console.log("alphaNumeric : " + alphaNumeric );

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