multiline-ternary

Enforce newlines between operands of ternary expressions

JavaScript allows operands of ternary expressions to be separated by newlines, which can improve the readability of your program.

For example:

var foo = bar > baz ? value1 : value2; 
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The above can be rewritten as the following to improve readability and more clearly delineate the operands:

 var foo = bar > baz ? value1 : value2; var foo = bar > baz ? value1 : value2; 
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Rule Details

This rule enforces or disallows newlines between operands of a ternary expression. Note: The location of the operators is not enforced by this rule. Please see the operator-linebreak rule if you are interested in enforcing the location of the operators themselves.

Options

This rule has a string option:

• "always" (default) enforces newlines between the operands of a ternary expression.
• "always-multiline" enforces newlines between the operands of a ternary expression if the expression spans multiple lines.
• "never" disallows newlines between the operands of a ternary expression.

always

This is the default option.

Examples of incorrect code for this rule with the "always" option:

/*eslint multiline-ternary: ["error", "always"]*/ foo > bar ? value1 : value2; foo > bar ? value : value2; foo > bar ? value : value2; 
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Examples of correct code for this rule with the "always" option:

/*eslint multiline-ternary: ["error", "always"]*/ foo > bar ? value1 : value2; foo > bar ? (baz > qux ? value1 : value2) : value3; foo > bar ? (baz > qux ? value1 : value2) : value3; 
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always-multiline

Examples of incorrect code for this rule with the "always-multiline" option:

/*eslint multiline-ternary: ["error", "always-multiline"]*/ foo > bar ? value1 : value2; foo > bar ? value1 : value2; foo > bar &&  bar > baz ? value1 : value2; 
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Examples of correct code for this rule with the "always-multiline" option:

/*eslint multiline-ternary: ["error", "always-multiline"]*/ foo > bar ? value1 : value2; foo > bar ? value1 : value2; foo > bar ? (baz > qux ? value1 : value2) : value3; foo > bar ? (baz > qux ? value1 : value2) : value3; foo > bar && bar > baz ? value1 : value2; foo > bar ? baz > qux ? value1 : value2 : value3; 
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never

Examples of incorrect code for this rule with the "never" option:

/*eslint multiline-ternary: ["error", "never"]*/ foo > bar ? value : value2; foo > bar ? value : value2; foo >  bar ? value1 : value2; 
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Examples of correct code for this rule with the "never" option:

/*eslint multiline-ternary: ["error", "never"]*/ foo > bar ? value1 : value2; foo > bar ? (baz > qux ? value1 : value2) : value3; foo > bar ? ( baz > qux ? value1 : value2 ) : value3; 
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When Not To Use It

You can safely disable this rule if you do not have any strict conventions about whether the operands of a ternary expression should be separated by newlines.

Compatibility

• JSCS: requireMultiLineTernary

Related Rules

• operator-linebreak

Version

This rule was introduced in ESLint v3.1.0.

Resources

• Rule source
• Tests source