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no-else-return

Disallow else blocks after return statements in if statements

πŸ”§ Fixable

Some problems reported by this rule are automatically fixable by the --fix command line option

If an if block contains a return statement, the else block becomes unnecessary. Its contents can be placed outside of the block.

function foo() {
if (x) {
return y;
} else {
return z;
}
}

Rule Details

This rule is aimed at highlighting an unnecessary block of code following an if containing a return statement. As such, it will warn when it encounters an else following a chain of ifs, all of them containing a return statement.

Options

This rule has an object option:

  • allowElseIf: true (default) allows else if blocks after a return
  • allowElseIf: false disallows else if blocks after a return

allowElseIf: true

Examples of incorrect code for this rule:

/*eslint no-else-return: "error"*/

function foo() {
if (x) {
return y;
} else {
return z;
}
}

function foo() {
if (x) {
return y;
} else if (z) {
return w;
} else {
return t;
}
}

function foo() {
if (x) {
return y;
} else {
var t = "foo";
}

return t;
}

function foo() {
if (error) {
return 'It failed';
} else {
if (loading) {
return "It's still loading";
}
}
}

// Two warnings for nested occurrences
function foo() {
if (x) {
if (y) {
return y;
} else {
return x;
}
} else {
return z;
}
}

Examples of correct code for this rule:

/*eslint no-else-return: "error"*/

function foo() {
if (x) {
return y;
}

return z;
}

function foo() {
if (x) {
return y;
} else if (z) {
var t = "foo";
} else {
return w;
}
}

function foo() {
if (x) {
if (z) {
return y;
}
} else {
return z;
}
}

function foo() {
if (error) {
return 'It failed';
} else if (loading) {
return "It's still loading";
}
}

allowElseIf: false

Examples of incorrect code for this rule:

/*eslint no-else-return: ["error", {allowElseIf: false}]*/

function foo() {
if (error) {
return 'It failed';
} else if (loading) {
return "It's still loading";
}
}

Examples of correct code for this rule:

/*eslint no-else-return: ["error", {allowElseIf: false}]*/

function foo() {
if (error) {
return 'It failed';
}

if (loading) {
return "It's still loading";
}
}

Version

This rule was introduced in ESLint v0.0.9.

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