# class Crystal::Macros::MacroId

- Crystal::Macros::MacroId
- Crystal::Macros::ASTNode
- Reference
- Object

##
Overview

A fictitious node representing an idenfitifer like, `foo`, `Bar` or `something_else`.

The parser doesn't create this nodes. Instead, you create them by invoking `#id` on some nodes. For example, invoking `#id` on a `StringLiteral` returns a `MacroId` for the string's content. Similarly, invoking ID on a `SymbolLiteral`, `Call`, `Var` and `Path` return MacroIds for the node's content.

This allows you to treat strings, symbols, variables and calls uniformly. For example:

    macro getter(name)
      def {{name.id}}
        @{{name.id}}
      end
    end

    getter unicorns
    getter :unicorns
    getter "unicorns"

All of the above macro calls work because we invoked `#id`, and the generated code looks like this:

    def unicorns
      @unicorns
    end

If we hand't use `#id`, the generated code would have been this:

    def unicorns
      @unicorns
    end

    def :unicorns
      @:unicorns
    end

    def "unicorns"
      @"unicorns"
    end

The last two definitions are invalid and so will give a compile-time error.

##
Defined in:

##
Instance Method Summary

- #+(other : StringLiteral | CharLiteral) : MacroId

  Similar to `String#+`.

- #=~(range : RegexLiteral) : BoolLiteral

  Similar to `String#=~`.

- #[](range : RangeLiteral) : MacroId

  Similar to `String#[]`.

- #capitalize : MacroId

  Similar to `String#capitalize`.

- #chars : Crystal::Macros::ArrayLiteral(CharLiteral)

  Similar to `String#chars`.

- #chomp : MacroId

  Similar to `String#chomp`.

- #downcase : MacroId

  Similar to `String#downcase`.

- #empty? : BoolLiteral

  Similar to `String#empty?`.

- #ends_with?(other : StringLiteral | CharLiteral) : BoolLiteral

  Similar to `String#ends_with?`.

- #gsub(regex : RegexLiteral, replacement : StringLiteral) : MacroId

  Similar to `String#gsub`.

- #id : MacroId

  Returns self.

- #includes?(search : StringLiteral | CharLiteral) : BoolLiteral

  Similar to `String#includes?`.

- #lines : Crystal::Macros::ArrayLiteral(StringLiteral)

  Similar to `String#lines`.

- #size : NumberLiteral

  Similar to `String#size`.

- #split(node : ASTNode) : Crystal::Macros::ArrayLiteral(StringLiteral)

  Similar to `String#split`.

- #split : Crystal::Macros::ArrayLiteral(StringLiteral)

  Similar to `String#split`.

- #starts_with?(other : StringLiteral | CharLiteral) : BoolLiteral

  Similar to `String#starts_with?`.

- #strip : MacroId

  Similar to `String#strip`.

- #tr(from : StringLiteral, to : StringLiteral) : MacroId

  Similar to `String#tr`.

- #upcase : MacroId

  Similar to `String#upcase`.

### Instance methods inherited from class `Crystal::Macros::ASTNode`

!=(other : ASTNode) : BoolLiteral !=, ==(other : ASTNode) : BoolLiteral ==, class_name : StringLiteral class_name, column_number : StringLiteral | NilLiteral column_number, end_column_number : StringLiteral | NilLiteral end_column_number, end_line_number : StringLiteral | NilLiteral end_line_number, filename : StringLiteral | NilLiteral filename, id : MacroId id, line_number : StringLiteral | NilLiteral line_number, raise(message) : NoReturn raise, stringify : StringLiteral stringify, symbolize : SymbolLiteral symbolize

### Instance methods inherited from class `Reference`

==(other : self)
==(other : JSON::Any)
==(other : YAML::Any)
==(other) ==, dup dup, hash(hasher) hash, inspect(io : IO) : Nil inspect, object_id : UInt64 object_id, pretty_print(pp) : Nil pretty_print, same?(other : Reference)
same?(other : Nil) same?, to_s(io : IO) : Nil to_s

### Constructor methods inherited from class `Reference`

new new

### Instance methods inherited from class `Object`

!=(other) !=, !~(other) !~, ==(other) ==, ===(other : JSON::Any)
===(other : YAML::Any)
===(other) ===, =~(other) =~, __crystal_pseudo_! : Bool __crystal_pseudo_!, __crystal_pseudo_as(type : Class) __crystal_pseudo_as, __crystal_pseudo_as?(type : Class) __crystal_pseudo_as?, __crystal_pseudo_is_a?(type : Class) : Bool __crystal_pseudo_is_a?, __crystal_pseudo_nil? : Bool __crystal_pseudo_nil?, __crystal_pseudo_responds_to?(name : Symbol) : Bool __crystal_pseudo_responds_to?, class class, dup dup, hash(hasher)
hash hash, inspect : String
inspect(io : IO) : Nil inspect, itself itself, not_nil! not_nil!, pretty_inspect(width = 79, newline = "\n", indent = 0) : String pretty_inspect, pretty_print(pp : PrettyPrint) : Nil pretty_print, tap(&) tap, to_json(io : IO)
to_json to_json, to_pretty_json(indent : String = " ")
to_pretty_json(io : IO, indent : String = " ") to_pretty_json, to_s : String
to_s(io : IO) : Nil to_s, to_yaml(io : IO)
to_yaml to_yaml, try(&) try, unsafe_as(type : T.class) forall T unsafe_as

### Class methods inherited from class `Object`

from_json(string_or_io, root : String)
from_json(string_or_io) from_json, from_yaml(string_or_io : String | IO) from_yaml

##
Instance Method Detail

def +(other : StringLiteral | CharLiteral) : MacroId #

Similar to `String#+`.

def =~(range : RegexLiteral) : BoolLiteral #

Similar to `String#=~`.

def [](range : RangeLiteral) : MacroId #

Similar to `String#[]`.

def capitalize : MacroId #

Similar to `String#capitalize`.

def chars : Crystal::Macros::ArrayLiteral(CharLiteral) #

Similar to `String#chars`.

def chomp : MacroId #

Similar to `String#chomp`.

def downcase : MacroId #

Similar to `String#downcase`.

def empty? : BoolLiteral #

Similar to `String#empty?`.

def ends_with?(other : StringLiteral | CharLiteral) : BoolLiteral #

Similar to `String#ends_with?`.

def gsub(regex : RegexLiteral, replacement : StringLiteral) : MacroId #

Similar to `String#gsub`.

def id : MacroId #

Returns self.

def includes?(search : StringLiteral | CharLiteral) : BoolLiteral #

Similar to `String#includes?`.

def lines : Crystal::Macros::ArrayLiteral(StringLiteral) #

Similar to `String#lines`.

def size : NumberLiteral #

Similar to `String#size`.

def split(node : ASTNode) : Crystal::Macros::ArrayLiteral(StringLiteral) #

Similar to `String#split`.

def split : Crystal::Macros::ArrayLiteral(StringLiteral) #

Similar to `String#split`.

def starts_with?(other : StringLiteral | CharLiteral) : BoolLiteral #

Similar to `String#starts_with?`.

def strip : MacroId #

Similar to `String#strip`.

def tr(from : StringLiteral, to : StringLiteral) : MacroId #

Similar to `String#tr`.

def upcase : MacroId #

Similar to `String#upcase`.