Build Range Table Using Functional Method Call

[Former Member]

I saw this snippet in ABAP Development discussion. The code was given by janis.bielajs

I am posting it here as the original discussion is now rejected, probably because of being too basic.

This snippet uses a fancy combination of functional method call and singleton pattern to build range for DELETE..WHERE field IN <range> statement.

1. *----------------------------------------------------------------------*
2. *       CLASS zcl_pattern_range DEFINITION
3. *----------------------------------------------------------------------*
4. *
5. *----------------------------------------------------------------------*
6. CLASS zcl_pattern_range DEFINITION
7.   FINAL
8.   CREATE PRIVATE .
10.   PUBLIC SECTION.
11.     TYPES: rt_patterns TYPE RANGE OF string .
12.     TYPES: rs_pattern TYPE LINE OF rt_patterns .
14.     CLASS-METHODS get_instance
15.       RETURNING value(ro_instance) TYPE REF TO zcl_pattern_range.
17.     METHODS:
18.      get_exclude_rng
19.        RETURNING value(rt_exclude_patterns) TYPE rt_patterns ,
20.      get_include_rng
21.        RETURNING value(rt_include_patterns) TYPE rt_patterns .
23.   PROTECTED SECTION.
25.   PRIVATE SECTION.
26.     CLASS-DATA mo_instance TYPE REF TO zcl_pattern_range.
28.     METHODS get_range
29.         IMPORTING i_sign TYPE c
30.         RETURNING value(rt_patterns) TYPE rt_patterns .
32. ENDCLASS.                    "zcl_pattern_range DEFINITION
34. *----------------------------------------------------------------------*
35. *       CLASS zcl_pattern_range IMPLEMENTATION
36. *----------------------------------------------------------------------*
37. *
38. *----------------------------------------------------------------------*
39. CLASS zcl_pattern_range IMPLEMENTATION.
41.   METHOD get_instance.
42.     IF mo_instance IS NOT BOUND .
43.       CREATE OBJECT mo_instance .
44.     ENDIF .
45.     ro_instance = mo_instance .
46.   ENDMETHOD.                    "get_instance
48.   METHOD get_range.
49.     DATA: ls_pattern TYPE rs_pattern .
50.     DATA: l_number TYPE i .
52.     REFRESH rt_patterns .
53.     ls_pattern-sign = i_sign .
54.     ls_pattern-option = 'CP' .
55.     WHILE l_number LE 9 .
56.       ls_pattern-low = l_number && '*' .
57. *      ls_pattern-low = |{ l_number }| && '*' .
58.       APPEND ls_pattern TO rt_patterns .
59.       ADD 1 TO l_number.
60.     ENDWHILE .
61.   ENDMETHOD.                    "get_range
63.   METHOD get_exclude_rng .
64.     REFRESH rt_exclude_patterns .
65.     rt_exclude_patterns = me->get_range( 'E' ).
66.   ENDMETHOD .                    "get_exclude_rng
68.   METHOD get_include_rng .
69.     REFRESH rt_include_patterns .
70.     rt_include_patterns = me->get_range( 'I' ).
71.   ENDMETHOD .                    "get_include_rng
73. ENDCLASS.                    "zcl_pattern_range IMPLEMENTATION
75. TYPES: BEGIN OF ts_string,
76.         string TYPE string,
77.       END OF ts_string .
78. DATA: gs_string TYPE ts_string .
79. DATA: gt_string TYPE STANDARD TABLE OF ts_string .
81. START-OF-SELECTION .
83.   REFRESH gt_string .
85.   gs_string-string = 'a12344'. APPEND gs_string TO gt_string.
86.   gs_string-string = '1234vb'. APPEND gs_string TO gt_string.
87.   gs_string-string = 'c42456d44'. APPEND gs_string TO gt_string .
89.   DELETE gt_string WHERE
90.     string IN zcl_pattern_range=>get_instance( )->get_exclude_rng( ).
91.   BREAK-POINT .
93.   REFRESH gt_string .
95.   gs_string-string = 'a12344'. APPEND gs_string TO gt_string.
96.   gs_string-string = '1234vb'. APPEND gs_string TO gt_string.
97.   gs_string-string = 'c42456d44'. APPEND gs_string TO gt_string .
99.   DELETE gt_string WHERE
100.     string NOT IN zcl_pattern_range=>get_instance( )->get_include_rng( ).

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