expected_ two_ map_ type_ arguments
Map literals require two type arguments or none, but {0} found.
Description
#The analyzer produces this diagnostic when a map literal has either one or more than two type arguments.
Example
#The following code produces this diagnostic because the map literal has three type arguments when it can have either two or zero:
var m = <int, String, int>{};
Common fixes
#Remove all except two of the type arguments:
var m = <int, String>{};
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