non_ bool_ expression
The expression in an assert must be of type 'bool'.
Description
#
The analyzer produces this diagnostic when the first expression in an
assert has a type other than
bool
.
Example
#
The following code produces this diagnostic because the type of
p
is
int
, but a
bool
is required:
void f(int p) {
assert(p);
}
Common fixes
#Change the expression so that it has the type bool
:
void f(int p) {
assert(p > 0);
}
Unless stated otherwise, the documentation on this site reflects Dart 3.9.2. Page last updated on 2025-9-1. View source or report an issue.