Converting between structurally compatible function types
Sebastian.Millies at softwareag.com
Mon Feb 23 17:36:27 UTC 2015
sorry for the noise, figured out how to use the identity function for this:
Function<Integer,Object> id = n -> n
g = id.compose(f);
From: lambda-dev [mailto:lambda-dev-bounces at openjdk.java.net] On Behalf Of Millies, Sebastian
Sent: Monday, February 23, 2015 6:32 PM
To: lambda-dev at openjdk.java.net
Subject: Converting between structurally compatible function types
I have a very basic question: why does the following not compile:
Function<String,Integer> f = s -> 1;
Function<String,Object> g = f;
After all, I would expect that anywhere where a function from String to arbitrary objects is required, I can supply a function to integers in particular.
I guess Java just sees the names are different, and that’s it?
How do I best convert between the two types?
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