EN_raw_literal_only_boolean_expressions

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              literal_only_boolean_expressions
  

Details about the 'literal_only_boolean_expressions' diagnostic produced by the Dart analyzer.

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                Lint rule
  

The Boolean expression has a constant value.

              Description

              #

              The analyzer produces this diagnostic when the value of the condition in
              an `if` or loop statement is known to be either always `true`
               or always
              `false`. An exception is made for a `while` loop whose condition is the
              Boolean literal `true`.

              Examples

              #

              The following code produces this diagnostic because the condition will
              always evaluate to `true`:

                dart

void f() {
  if (true) {
    print('true');
  }
}

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              The lint will evaluate a subset of expressions that are composed of
              constants, so the following code will also produce this diagnostic because
              the condition will always evaluate to `false`:

                dart

void g(int i) {
  if (1 == 0 || 3 > 4) {
    print('false');
  }
}

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              Common fixes

              #

              If the condition is wrong, then correct the condition so that it's value
              can't be known at compile time:

                dart

void g(int i) {
  if (i == 0 || i > 4) {
    print('false');
  }
}

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              If the condition is correct, then simplify the code to not evaluate the
              condition:

                dart

void f() {
  print('true');
}

                content_copy

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                Unless stated otherwise, the documentation on this site reflects Dart 3.13.3. Report an issue.