prefer_conditional_expressions

v1.0.0WarningControl Flow

This rule flags an if/else that does nothing but assign or return two values.

Six lines to choose between two strings buries the one thing that varies. A conditional expression puts the choice and both outcomes on one line, and makes it obvious that every path assigns exactly once — which the block form only implies.

Only the two shapes where the rewrite is exact are reported: both branches return, or both assign to the same target with the same operator. A branch with two statements, different targets, different operators, a missing else or an else if chain is left alone, since collapsing it would change what the code does.

This rule is in the pedantic preset.

Don’t

if (isActive) {
  label = 'On';
} else {
  label = 'Off';
}

Do

label = isActive ? 'On' : 'Off';

Enabling this rule

This rule is in the pedantic preset, so it is enabled by preset: pedantic or by name:

many_lints.yaml

rules:
  prefer_conditional_expressions:
    enabled: true

Turning this rule off

To disable this rule:

many_lints.yaml

rules:
  prefer_conditional_expressions: false

To keep the rule on but skip certain paths, use per-rule exclude.

Related rules

• avoid_nested_conditional_expressions — Flag a conditional nested inside another.
• prefer_switch_expression — Suggest converting switch statements to switch expressions.
• prefer_switch_with_enums — Use a switch instead of an if-else chain over enum constants.
• avoid_contradictory_expressions — Detect logical AND conditions that always evaluate to false.