why expression with 'undefined' does not return boolean
93881
Javascript AND operator within assignment
84817
What is the symbol you'd use for Boolean results?
84421
variable === undefined vs. typeof variable === "undefined"
38794
Validate a Boolean expression with brackets in C#
69801
What does it mean when ST_Equals returns false and `=` returns true?
151096
Why does the expression 0 < 0 == 0 return False in Python?
665
Which equals operator (== vs ===) should be used in JavaScript comparisons?
15796
the operation of "=" in javascript
96061
Console returns undefined
105287
(Why) is using an uninitialized variable undefined behavior?
151837
Why doesn't the boolean modifier work for me?
132708
Function returning Null along with other unexpected expressions
155520
Why does $('#id') return true if id doesn't exist?
147617
Javascript ternary operator
113905
How can I check whether a variable is defined in JavaScript?
121296
How to pass the value 'undefined' to a function with multiple parameters?
576
How can I check for an empty/undefined/null string in JavaScript?