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JavaScript: Truncate a string up to a specified length

JavaScript fundamental (ES6 Syntax): Exercise-117 with Solution

Write a JavaScript program to truncate a string up to a specified length.

Note: Determine if the string's length is greater than num. Return the string truncated to the desired length, with '...' appended to the end or the original string.

  • Determine if String.prototype.length is greater than num.
  • Return the string truncated to the desired length, with '...' appended to the end or the original string.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const truncateString = (str, num) =>
  str.length > num ? str.slice(0, num > 3 ? num - 3 : num) + '...' : str;

console.log(truncateString('boomerang', 7));

Sample Output:

boom...

Pictorial Presentation:

JavaScript Fundamental: Truncate a string up to a specified length.

Flowchart:

flowchart: Truncate a string up to a specified length

Live Demo:

See the Pen javascript-basic-exercise-117-1 by w3resource (@w3resource) on CodePen.


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Previous: Write a JavaScript program to check if the predicate (second argument) is truthy on all elements of a collection (first argument).
Next: Write a JavaScript program to apply a function against an accumulator and each key in the object (from left to right).

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JavaScript: Tips of the Day

Returns an array of n-tuples of consecutive elements

Example:

const tips_arr = (n, arr) =>  n > arr.length ? [] : arr.slice(n - 1).map((v, i) =>[...arr.slice(i, i + n - 1), v]);
console.log(tips_arr(2, [1, 2, 3, 4, 5])); 
console.log(tips_arr(3, [1, 2, 3, 4, 5]));
console.log(tips_arr(5, [1, 2, 3, 4]));

Output:

[[1, 2], [2, 3], [3, 4], [4, 5]]
[[1, 2, 3], [2, 3, 4], [3, 4, 5]]
[]