class Crystal::Macros::FunDef

• Crystal::Macros::FunDef
• Crystal::Macros::ASTNode

Overview

A function declaration inside a lib, or a top-level C function definition.

Every function node is equivalent to:

fun {{ node.name }} {% if real_name = node.real_name %}= {{ real_name }}{% end %}(
  {% for arg in node.args %} {{ arg }}, {% end %}
  {% if node.variadic? %} ... {% end %}
) {% if return_type = node.return_type %}: {{ return_type }}{% end %}
{% if node.has_body? %}
  {{ body }}
end
{% end %}

Defined in:

Instance Method Summary

• #args : ArrayLiteral(Arg)

  Returns the parameters of the function.

• #body : ASTNode | Nop

  Returns the body of the function, if any.

• #has_body? : BoolLiteral

  Returns whether this function has a body.

• #name : MacroId

  Returns the name of the function in Crystal.

• #real_name : StringLiteral | Nop

  Returns the real C name of the function, if any.

• #return_type : ASTNode | Nop

  Returns the return type of the function, if specified.

• #variadic? : BoolLiteral

  Returns whether the function is variadic.

Instance Method Detail

macro body_class(x)
  {{ (x.is_a?(LibDef) ? x.body : x).body.class_name }}
end

body_class(lib MyLib
  fun foo
end) # => "Nop"

body_class(fun foo
end) # => "Nop"

macro has_body(x)
  {{ (x.is_a?(LibDef) ? x.body : x).has_body? }}
end

has_body(lib MyLib
  fun foo
end) # => false

has_body(fun foo
end) # => true