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Tanvir Ahmed
Tanvir Ahmed

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Exploring the Core of true value vs false value in JavaScript...

Truthy Value

In JavaScript, a truthy value is any value that is considered true when evaluated in a Boolean context. Values that are not falsy are considered truthy.

Example of truthy values:

  • Any non-zero number (1,-5,3.14)
  • Non-empty strings ("hello" )
  • space value(" ")
  • Objects ({}, [])
  • The boolean true

Now Example,

1.Checking a Non-empty String:
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  • Explanation: The string "JavaScript" is a non-empty string, so it evaluates to true.

2.Checking a String with a Space:
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  • Explanation: The string " " (a string containing a space) is also a non-empty string, which evaluates to true.

3.Checking a Positive Number:
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  • Explanation: The number 100 is a non-zero number, so it evaluates to true.

4.Checking a Negative Number:
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  • Explanation: The number -5 is also a non-zero number, making it truthy.

5.Checking an Empty Array & Object:
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  • Explanation: An empty array [] is considered truthy in JavaScript.
  • Explanation: An empty object {} is also considered truthy

6.Checking the Boolean True:
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  • Explanation: The boolean value true is, by definition, truthy.

Falsy Value

A falsy value is something which evaluates to FALSE, for instance when checking a variable.

Example of falsy values:

  • 0 zero && (-0) negative zero
  • empty strings ("" )
  • null,undefine & Nan
  • The boolean false

Now Example,

Part01
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Part02
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