Check out example codes for "typescript initialize map inline". It will help you in understanding the concepts better.

Code Example 1

new Map<string, string>([
  ["key1", "value1"],
  ["key2", "value2"]
]);

new Map<string, Array<string>>([
  ["key1", ["value1", "value2"]],
  ["key2", ["value3"]]	
]);

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