Web-Related Terms Beginning with N
Named Capturing Group (RegExp)
The named capturing group operator (?<name>) defines the name of a capturing group.
Named Function
A named function is a function with a name.
Namespace
A namespace is a named container (variable) used to store objects of any type.
Negative Lookahead (RegExp)
Regular expression's negative lookahead operator (p(?!sp)) asserts that you wish to find a RegExp pattern that is not followed by another pattern.
Negative Lookbehind (RegExp)
A regular expression's negative lookbehind operator ((?<!sp)p) asserts that you wish to find a RegExp pattern that is not preceded by another pattern.
Networking
Networking means connecting things.
New Line Character
The new line character (\n) helps create line breaks in strings.
node_modules
node_modules is a folder NPM uses to store all the packages downloaded locally for your project.
Non-Assignment Expression (JS)
A non-assignment expression is a piece of code that does not assign its evaluated value to any variable (or property).
Non-Capturing Group (RegExp)
A regular expression's non-capturing group operator (?:) allows you to group a pattern without capturing (saving) it.
Non-Greedy Quantifiers (RegExp)
Non-greedy quantifiers are quantifier operators that will automatically find the shortest part of the given string that matches the specified RegExp pattern.
Non-Primitive Data (JS)
Non-primitive data is a JavaScript value that can contain multiple other values.
Non-Restartable Iterator (JS)
A non-restartable iterator is an object you can use only once. Any subsequent iteration after the first will return nothing.
An example of a non-restartable object is matchAll()'s returned value.
Example
// Match a regular expression's pattern against a string and assign the result to a variable:
const result = "Tuesday".matchAll(/day/g);
// Print the result variable's content on the console:
console.log(result); // RegExp String Iterator { }
// Print the result variable as an array on the console:
for (const arrayVersion of result) {
console.log(arrayVersion); // ['day', index: 4, input: 'Tuesday', groups: undefined]
}
// Print the result variable as an array on the console again:
for (const arrayVersion of result) {
console.log(arrayVersion); // undefined
}
You can see that the second for...of loop statement printed undefined. This is because the result variable contains a non-restartable iterator object which you can use only once.
To reuse the result variable, use the spread operator to convert the iterator from a non-restartable to a restartable object.
Example
// Match a regular expression's pattern against a string and assign the result to a variable:
const result = [..."Tuesday".matchAll(/day/g)];
// Print the result variable's content on the console:
console.log(result); // [['day', index: 4, input: 'Tuesday', groups: undefined]]
// Print the result variable as an array on the console:
for (const arrayVersion of result) {
console.log(arrayVersion); // ['day', index: 4, input: 'Tuesday', groups: undefined]
}
// Print the result variable as an array on the console again:
for (const arrayVersion of result) {
console.log(arrayVersion); // ['day', index: 4, input: 'Tuesday', groups: undefined]
}
Non-Word Boundary (RegExp)
Regular expression's non-word boundary operator (\B) asserts that you wish to find the RegExp pattern that is not at the starting (or ending) boundary of a word.
NOT (RegExp)
A regular expression's NOT operator ([^abc]) defines the set of characters you do not wish to find in a single character's position.
NOT Equal to Operator (JS)
The NOT equal to operator (!=) checks if its two operands are not of equal value. If so, the Boolean value true gets returned. Otherwise, the computer will return false.
NOT Operator (JS)
The NOT operator (!) is used to negate the Boolean value of an expression. In other words, it converts true to NOT true and false to NOT false.
NOT Strictly Equal to Operator (JS)
The Not strictly equal to operator (!==) checks if its two operands are strictly not of equal type and equal value. If so, the Boolean value true gets returned. Otherwise, the computer will return false.
NPM
NPM (Node Package Manager) is a package manager (an alternative to Yarn) that automatically helps find and execute a specified package.
NPX
NPX is node's package runner tool. It helps to automatically find and execute a specified package.
Null (JS)
Use null to indicate an intentional absence of a value.
Nullish Coalescing Operator (JS)
The nullish coalescing operator (??) checks if its left-hand side operand is undefined or null. If so, it returns its right-hand side operand. Otherwise, it produces its left-hand side operand.
Number
A number is an idea of quantity.
Number (JS)
A number is a double-precision 64-bit floating-point arithmetic data.
Number() in JavaScript
Number() converts its argument to a Number type or NaN.
Number.isInteger() in JavaScript
Number.isInteger() checks if its argument is an integer.
Numeral
A numeral is the written form of a number.