Comments

* Line Comments
" End of line comment used as line comment.
value = 1. " End of line comment

DATA:
  "! ABAPDoc comment
  value TYPE i.

Strings

my_string = 'Simple string'.
my_string = 'String with an escaped '' inside'.
my_string = |A string template: { nvalue } times|.
my_string = |A string template: { nvalue } times|.
my_string = |Characters \|, \{, and \} have to be escaped by \\ in literal text.|. 

Numbers and Operators

value = 001 + 2 - 3 * 4 / 5 ** 6.

IF value < 1 OR
   value = 2 OR
   value > 3 OR
   value <> 4 OR
   value <= 5 OR
   value >= 6.
ENDIF.

" Dynamic object assignment (with type cast check)
lo_interface ?= lo_class.

Structures and Classes

DATA:
  BEGIN OF my_structure,
    scomponent TYPE i,
  END OF my_structure.

CLASS lcl_my_class DEFINITION.
  PUBLIC SECTION.
    METHODS my_method
      RETURNING
        VALUE(ret_value) TYPE i.
ENDCLASS.

CLASS lcl_my_class IMPLEMENTATION.
  METHOD my_method.
    ret_value = 1.
  ENDMETHOD
ENDCLASS.

DATA lo_instace TYPE REF TO lcl_my_class.

CREATE OBJECT lo_instace.

my_structure-component = lo_instace->my_method( ).