Are Clojure macros hygienic?

Macro Hygiene and gensym Such macros are known as unhygienic macros. Clojure does not implement a full solution to hygienic macros but provides solutions to the biggest pitfalls of unhygienic macros by enforcing several restrictions: Symbols within a syntax quoted form are namespace-qualified.

When should I use Elixir macros?

You can use macros to generate boilerplate code, create new language features, or even build domain-specific languages (DSLs). Actually, a lot of the language constructs that we regularly use in Elixir such as def , defmodule , if , and others are macros.

What is a macro in Clojure?

Clojure has a programmatic macro system which allows the compiler to be extended by user code. Macros can be used to define syntactic constructs which would require primitives or built-in support in other languages. Many core constructs of Clojure are not, in fact, primitives, but are normal macros.

What is a macro in Elixir?

12.3) Macros are compile-time constructs that are invoked with Elixir’s AST as input and a superset of Elixir’s AST as output. To learn more about Elixir’s AST and how to build them programmatically, see quote/2 . …

What is __ module __ In Elixir?

__MODULE__ is a compilation environment macros which is the current module name as an atom. Now you know alias __MODULE__ just defines an alias for our Elixir module. This is very useful when used with defstruct which we will talk about next.

What is DEFN Clojure?

First Class Functions They can be assigned as values, passed into functions, and returned from functions. It’s common to see function definitions in Clojure using defn like (defn foo … ​)) fn returns a function object. defn returns a var which points to a function object.

What is binding in Clojure?

3. 111. let creates a lexically scoped immutable alias for some value. binding creates a dynamically scoped binding for some Var . Dynamic binding means that the code inside your binding form and any code which that code calls (even if not in the local lexical scope) will see the new binding.

What exactly is metaprogramming?

Metaprogramming is a programming technique in which computer programs have the ability to treat other programs as their data. Metaprogramming can be used to move computations from run-time to compile-time, to generate code using compile time computations, and to enable self-modifying code.