assert

Platform (all, jvm, js): all
Extension (none, kotlin 1.3): none

Code related feature

Following the things you need to do:

• see TODOs in MapToContainInOrderOnlyKeyValueExpectationsSpec

Your first contribution?

• Write a comment I'll work on this if you would like to take this issue over.
  This way we get the chance to revise the description in case things have c

Add the following extensions methods for dictionaries:

var dictionary = new Dictionary<string, string>
{
    ["key1"] = "value1",
    ["key2"] = "value2",
};

dictionary.Throw().IfContainsKey("key1");
dictionary.Throw().IfNotContainsKey("key3");

And the corresponding dictionary properties extension methods:

var dictionary = new Dictionary<string, string

Describe the solution you'd like
Add compile-time String concactenation support in messages. Currently, constraits's message with concactenated strings can only be evaluated at runtime (gives the <Unknown> message at compile-time instead).

Describe alternatives you've considered
A potential solution would be to create our own instance of FromExpr[String] based on the stdlib's one