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Warning: unreachable code after return statement

return JavaScript unreachable code after return statement

Warning: unreachable code after return statement (Firefox)

return

return return

return return return return

return

js
function f() {
  let x = 3;
  x += 4;
  return x;   // return 
  x -= 3;     // 
}

function g() {
  return     //  `return;`
    3 + 4;   // 
}

js
function f() {
  let x = 3;
  x += 4;
  x -= 3;
  return x; // OK
}

function g() {
  return 3 + 4 // OK
}

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    99. TypeError: already executing generator
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    113. TypeError: cyclic object value
    114. TypeError: derived class constructor returned invalid value x
    115. TypeError: getting private setter-only property
    116. TypeError: Initializing an object twice is an error with private fields/methods
    117. TypeError: invalid 'instanceof' operand 'x'
    118. TypeError: invalid Array.prototype.sort argument
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    127. TypeError: WeakSet key/WeakMap value 'x' must be an object or an unregistered symbol
    128. X.prototype.y called on incompatible type
    129. URIError: malformed URI sequence
    130. Warning: -file- is being assigned a //# sourceMappingURL, but already has one
    131. Warning: unreachable code after return statement
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