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@param

Tag type: block tag

TSDoc standardization: core

Syntax:

  • @param NAME - DESCRIPTION

The @param tag is used to document a function or method parameter. The @param tag is followed by the parameter name, followed by a hyphen, followed by a description. Being a block tag, @param introduces a TSDoc section that contains all comment text up until the next block tag.

NOTE: JSDoc’s version of the @param tag optionally allows type information to be specified in curly braces. For example:

// NOT SUPPORTED BY API EXTRACTOR

/**
 * @param {string} somebody - Somebody's name.
 */
function sayHello(somebody) {
  alert('Hello ' + somebody);
}

API Extractor does not support this {string} notation, since its grammar is complex, and the type system it implements is fairly rudimentary compared to TypeScript’s. For TypeScript source code, the parameter type information is already fully expressed in the code, and thus it would be redundant to try to express it in a doc comment.

Usage example:

/** @public */
export class Statistics {
  /**
   * Returns the average of two numbers.
   *
   * @remarks
   * This method is part of the {@link core-library#Statistics | Statistics subsystem}.
   *
   * @param x - The first input number
   * @param y - The second input number
   * @returns The arithmetic mean of `x` and `y`
   */
  public static getAverage(x: number, y: number): number {
    return (x + y) / 2.0;
  }
}

See also