const_ spread_ expected_ map
A map is expected in this spread.
Description
#The analyzer produces this diagnostic when the expression of a spread operator in a constant map evaluates to something other than a map.
Example
#
The following code produces this diagnostic because the value of
map1
is
null
, which isn't a map:
const dynamic map1 = 42;
const Map<String, int> map2 = {...map1};
Common fixes
#Change the expression to something that evaluates to a constant map:
const dynamic map1 = {'answer': 42};
const Map<String, int> map2 = {...map1};
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