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0 pointskyllo11y ago0 comments

An anonymous inner class with only one method. The "inner" is important. It still has to exist inside of an explicitly declared class. Also, a variable holding a reference to a lambda function cannot be called as a function (no function pointers).

Contrast with JavaScript, where functions are first-class, can be declared at top level, can be passed as arguments to and returned by other functions, can be called by dereferencing a variable, can be nested, can be partially applied, etc.

The minimal syntactic sugar for anonymous inner classes added in Java 8 doesn't even begin to approach the power of the function support in languages like JavaScript. Language-level support for this stuff matters.

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2 comments · 1 top-level

empthought11y ago· 1 in thread

They have exactly the same "power," they're just spelled differently. "func()" doesn't let you do anything that you can't do with "callable.call()". It's trivial to do everything that isn't syntactic sugar (for example, partial application, passing as arguments for abstraction) that you mention in Java, if a bit tedious (and often pointless, since the standard APIs generally weren't designed with that in mind.) _A Little Java, A Few Patterns_ came out in 1998; give it a read.

kylloOP11y ago

The fact you put the word "power" in scare quotes indicates to me that you don't understand what it means in this context. Here, have a pg essay: http://www.paulgraham.com/power.html

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