Constructor Expressions

Constructor Expressions
- Introduction
- VALUE
- CORRESPONDING
- NEW
- CONV
- EXACT
- REF
- CAST
- COND
- SWITCH
- FILTER
- REDUCE
- Iteration Expressions with FOR
- LET Expressions
- Executable Example

Introduction

Constructor expressions include a constructor operator followed by the specification of a data type or object type (or a # character that stands for such a type) and specific parameters specified within parentheses. Example using the VALUE operator:
```
... VALUE string( ... ) ...
... VALUE #( ... ) ...
```
As the name implies, these expressions construct results of a specific type and their content. Either the type is specified explicitly before the first parenthesis or the said # character can be specified if the type can be derived implicitly from the operand position. The # character symbolizes the operand type. If no type can be derived from the operand position, for some constructor operators, the type can also be derived from the arguments in the parentheses.
Why use them? Constructor expressions can make your code leaner and more readable since you can achieve the same with fewer statements.
Apart from the concept of deriving types from the context, another concept is very handy particularly in this context: Inline declaration.
- This means that you can declare a variable using DATA(var) (or, in newer ABAP releases, an immutable variable FINAL(var)) as an operand in the current write position. In doing so, such a variable declared inline can be given the appropriate type and result of the constructor expression in one go: DATA(dec) = VALUE decfloat34( '1.23' ).

✔️ Hint
The construction of a result, i. e. a target data object, implies that the data object is initialized. However, for some constructor operators, there is an addition with which the initialization can be avoided.

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VALUE

Expressions with the VALUE operator construct a result in place based on a data type.
This result can be initial values for any non-generic data types, structures or internal tables.

💡 Note
Elementary data types and reference types cannot be explicitly specified for the construction of values here.

Regarding the type specifications before and parameters within the parentheses:
- No parameter specified within the parentheses: The return value is set to its type-specific initial value. This is possible for any non-generic data types. See more information here.
- Structured and internal table type before the parentheses or # stands for such types: Individual components of structures can be specified as named arguments while each component of the return value can be assigned a data object that has the same data type as the component, or whose data type can be converted to this data type. See more information here. To construct internal tables, you have multiple options, for example, you can add individual table lines using an inner pair of parentheses. More syntax options, for example, using the additions BASE and FOR are possible, too. See more information here.

Example: Structure

"Creating a structured type
TYPES: BEGIN OF struc_type,
         a TYPE i,
         b TYPE c LENGTH 3,
       END OF struc_type.

DATA struc TYPE struc_type. "Structured data object

struc = VALUE #( a = 1 b = 'aaa' ). "Deriving the type using #

As mentioned above, the concept of inline declarations enters the picture here, which simplifies ABAP programming. You can construct a new data object (for example, using DATA(...)), provide the desired type with the constructor expression and assign values in one go.

"Explicit type specification needed
DATA(structure) = VALUE struc_type( a = 2 b = 'bbb' ).

Note that initial values can be created by omitting the specification of components or by providing no content within the parentheses.

"Component b not specified, b remains initial
struc = VALUE #( a = 2 ).

"Explicit setting of initial value for a component
struc = VALUE #( a = 1 b = value #( ) ).

"The whole structure is initial
struc = VALUE #( ).

"Creating initial values for an elementary data type
DATA num1 TYPE i.

num1 = VALUE #( ).

"Inline declaration
DATA(num2) = VALUE i( ).

Regarding internal tables, the line specifications are enclosed in an inner pair of parentheses ( ... ). In the following example, three lines are added to an internal table.

"Creating an internal table type and an internal table
TYPES tab_type TYPE TABLE OF struc_type WITH EMPTY KEY.
DATA itab TYPE tab_type.

"Filling the internal table using the VALUE operator with #
itab = VALUE #( ( a = 1 b = 'aaa' )
                ( a = 2 b = 'bbb' )
                ( a = 3 b = 'ccc' ) ).

"Internal table declared inline, explicit type specification
DATA(itab2) = VALUE tab_type( ( a = 1 b = 'aaa' )
                              ( a = 2 b = 'bbb' )
                              ( a = 3 b = 'ccc' ) ).

"Unstructured line types work without component names.
"Here, the internal table type is a string table.
DATA(itab3) = VALUE string_table( ( `abc` ) ( `def` ) ( `ghi` ) ).

In case of deep and nested structures or deep tables, the use of VALUE expressions is handy. The following example demonstrates a nested structure.

"Creating a nested structure
DATA: BEGIN OF nested_struc,
        a TYPE i,
        BEGIN OF struct,
          b TYPE i,
          c TYPE c LENGTH 3,
        END OF struct,
      END OF nested_struc.

"Filling the deep structure
nested_struc = VALUE #( a = 1 struct = VALUE #( b = 2 c = 'abc' ) ).

BASE addition: A constructor expression without the BASE addition initializes the target variable. Hence, you can use the addition if you do not want to construct a structure or internal table from scratch but keep existing content.

"Filling structure
struc = VALUE #( a = 1 b = 'aaa' ).

"struc is not initialized, only component b is modified, value of a is kept
struc = VALUE #( BASE struc b = 'bbb' ).

"Filling internal table with two lines
itab = VALUE #( ( a = 1 b = 'aaa' )
                ( a = 2 b = 'bbb' ) ).

"Two more lines are added instead of initializing the internal table
itab = VALUE #( BASE itab
                ( a = 3 b = 'ccc' )
                ( a = 4 b = 'ddd' ) ).

LINES OF addition: All or some lines of another table can be included in the target internal table (provided that they have appropriate line types):

itab = VALUE #( ( a = 1 b = 'aaa' )
                ( a = 2 b = 'bbb' )
                ( LINES OF itab2 )    "All lines of itab2
                ( LINES OF itab3 FROM 2 TO 5 ) ).  "Specific lines of itab3

Using the inline construction of structures and internal tables, you can avoid the declaration of extra variables in many contexts, for example, ABAP statements like MODIFY for modifying internal tables or ABAP SQL statements like MODIFY (which is not to be confused with the ABAP statement having the same name) for modifying database tables.

Examples:

"ABAP statements
"Modifiying individual internal table entries based on a structure created inline

"Modifying a table line
MODIFY TABLE some_itab FROM VALUE #( a = 1 ... ).

"Inserting a table line
INSERT VALUE #( a = 2 ... ) INTO TABLE some_itab.

"Deleting a table line
DELETE TABLE some_itab FROM VALUE #( a = 3 ).

"ABAP SQL statement
"Modifying multiple database table entries based on an internal table
"constructed inline within a host expression
MODIFY zdemo_abap_carr FROM TABLE @( VALUE #(
            ( carrid = 'XY'
              carrname = 'XY Airlines'
              currcode = 'USD'
              url =  'some_url' )
            ( carrid = 'ZZ'
              carrname = 'ZZ Airways'
              currcode = 'EUR'
              url =  'some_url' ) ) ).

💡 Note
Some of the additions and concepts mentioned here are also valid for other constructor expressions further down but not necessarily mentioned explicitly. See the details on the syntactical options of the constructor operators in the ABAP Keyword Documentation.

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CORRESPONDING

Expressions with the CORRESPONDING operator construct structures and internal tables based on a data type (i. e. a table type or structured type).
The components or columns of the target data object are filled using assignments of the parameters specified within the parentheses.
The assignments are made using identical names or based on mapping relationships
Note: Pay attention to the assignment and conversion rules to avoid errors when using the operator. Consider, for example, the impact of assigning the values of identically named fields having different types (e. g. one field is of type c and another field is of type string).

The following table includes a selection of various possible additions to this constructor operator. There are more variants available like the addition EXACT, using a lookup table, the option of discarding duplicates or RAP-specific variants that are not part of this cheat sheet. Find the details in this topic.

Addition	Details
`BASE`	Keeps original values. Unlike, for example, the operator `VALUE`, a pair of parentheses must be set around `BASE`.
`MAPPING`	Enables the mapping of component names, i. e. a component of a source structure or source table can be assigned to a differently named component of a target structure or target table (e. g. `MAPPING c1 = c2`).
`EXCEPT`	You can specify components that should not be assigned content in the target data object. They remain initial. In doing so, you exclude identically named components in the source and target object that are not compatible or convertible from the assignment to avoid syntax errors or runtime errors.
`DEEP`	Relevant for deep tabular components. They are resolved at every hierarchy level and identically named components are assigned line by line.
`[DEEP] APPENDING`	Relevant for (deep) tabular components. It ensures that the nested target tables are not deleted. The effect without `DEEP` is that lines of the nested source table are added using `CORRESPONDING` without addition. The effect with `DEEP` is that lines of the nested source table are added using `CORRESPONDING` with the addition `DEEP`.

See the executable example for demonstrating the effect of the variants:

"Assignment of a structure/internal table to another one having a different type
struc2 = CORRESPONDING #( struc1 ).

tab2 = CORRESPONDING #( tab1 ).

"BASE keeps original content, does not initialize the target
struc2 = CORRESPONDING #( BASE ( struc2 ) struc1 ).

tab2 = CORRESPONDING #( BASE ( tab2 ) tab1 ).

"MAPPING/EXACT are used for mapping/excluding components in the assignment
struc2 = CORRESPONDING #( struc1 MAPPING comp1 = comp2 ).

tab2 = CORRESPONDING #( tab1 EXCEPT comp1 ).

"Complex assignments with deep components using further additions
st_deep2 = CORRESPONDING #( DEEP st_deep1 ).

st_deep2 = CORRESPONDING #( DEEP BASE ( st_deep2 ) st_deep1 ).

st_deep2 = CORRESPONDING #( APPENDING ( st_deep2 ) st_deep1 ).

st_deep2 = CORRESPONDING #( DEEP APPENDING ( st_deep2 ) st_deep1 ).

✔️ Hint
CORRESPONDING operator versus MOVE-CORRESPONDING: Although the functionality is the same, note that, as the name implies, constructor operators construct and - without the addition BASE - target objects are initialized. Hence, the following two statements are not the same:
struc2 = CORRESPONDING #( struc1 ).

"Not matching components are not initialized
MOVE-CORRESPONDING struc1 TO struc2.

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NEW

Using the instance operator NEW, you can create anonymous data objects or instances of a class and also assign values to the new object. As a result, you get a reference variable that points to the created object. In doing so, the operator basically replaces CREATE DATA and CREATE OBJECT.
For the type specification preceding the parentheses, you can use
- non-generic data types which creates a data reference variable pointing to the anonymous data object.
- classes which creates objects of these classes. The result is an object reference variable pointing to an object.
Regarding the created object reference variables, you can use the object component selector -> in certain contexts to ...
- point to a class attribute: ... NEW class( ... )->attr
- introduce standalone and functional method calls, including chained method calls which is a big advantage because you do not need to declare an extra variable: ... NEW class( ... )->meth( ... ) ...
Regarding the type specifications before and parameters within the parentheses:
- No parameter specified within the parentheses: An anonymous data object retains its type-specific initial value. In case of classes, no parameter specification means that no values are passed to the instance constructor of an object. However, in case of mandatory input parameters, the parameters must be specified.
- Single parameter specified: If the type specified before the parentheses is a non-generic elementary, structured, table, or a reference type (or such a type can be derived using #), a single data object can be specified as an unnamed argument. Note the assignment rules regarding the value assignments within the parentheses and that a constructor expression itself can be specified there.
- Structures and internal tables specified: If the type specified before the parentheses is a structured data type or # stands for it, you can specify the individual components as named arguments (comp1 = 1 comp2 = 2 ...; see more information here). For the construction of anonymous internal tables, multiple options are available. Among them, there is the use of LET and FOR expressions and others. See more details here.
- Classes: As mentioned, non-optional input parameters of the instance constructor of the instantiated class must be filled. No parameters are passed for a class without an explicit instance constructor. See more information: here.

Examples:

"Data references
"Declaring data reference variables
DATA dref1 TYPE REF TO i.    "Complete type
DATA dref2 TYPE REF TO data. "Generic type

"Creating anonymous data objects
"Here, no parameters are specified within the parentheses meaning the
"data objects retain their initial values.
dref1 = NEW #( ).
dref2 = NEW string( ).

"Assigning single values; specified as unnamed data objects
dref1 = NEW #( 123 ).
dref2 = NEW string( `hallo` ).

"Using inline declarations to omit a prior declaration of a variable
DATA(dref3) = NEW i( 456 ).

DATA text TYPE string VALUE `world`.

"Another constructor expression specified within the parentheses
dref2 = NEW string( `Hello ` && text && CONV string( '!' ) ).

DATA dref4 TYPE REF TO string_table.
dref4 = NEW #( VALUE string_table( ( `a` ) ( `b` ) ) ).

"Structured type; named arguments within the parentheses
DATA(dref5) = NEW scarr( carrid = 'AA' carrname = 'American Airlines' ).

"Object references
"Declaring object reference variables
DATA oref1 TYPE REF TO cl1. "Assumption: class without constructor implementation
DATA oref2 TYPE REF TO cl2. "Assumption: class with constructor implementation

"Creating instances of classes
oref1 = NEW #( ).

"Listing the parameter bindings for the constructor method
"If there is only one parameter, the explicit specification of the
"parameter name is not needed and the value can be specified directly
oref2 = NEW #( p1 = ... p2 = ... ).

"Using inline declaration
DATA(oref3) = NEW cl2( p1 = ... p2 = ... ).

"Method chaining
... NEW some_class( ... )->meth( ... ).

"Chained attribute access
... NEW some_class( ... )->attr ...

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CONV

The CONV operator enforces conversions from one type to another and creates an appropriate result.
Note that the conversion is carried out according to conversion rules.
- Further special rules apply if the constructor expression is passed to an actual parameter with a generically typed formal parameter.
The operator is particularly suitable for avoiding the declaration of helper variables.

Examples:

"Result: 0.2
DATA(a) = CONV decfloat34( 1 / 5 ).

"Comparison with an expression without CONV; the result is 0, the data type is i
DATA(b) = 1 / 5.

Excursion: As outlined above, you can construct structures and internal tables using the VALUE operator. Using this operator for constructing elementary data objects is not possible apart from creating a data object with an initial value, for example DATA(str) = VALUE string( ).. The CONV operator closes this gap. However, in some cases, the use of CONV is redundant.

DATA(c) = CONV decfloat34( '0.4' ).

"Instead of
DATA d TYPE decfloat34 VALUE '0.4'.
"or
DATA e TYPE decfloat34.
e = '0.4'.

"Redundant conversion
"Derives the string type automatically
DATA(f) = `hallo`.

"Produces a syntax warning
"DATA(g) = CONV string( `hallo` ).

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EXACT

The EXACT operator enforces either a lossless assignment or a lossless calculation depending on the data object specified within the parentheses and creates an appropriate result.
In case of calculations, rules of lossless assignments apply. In other cases, the result is created according to the conversion rules mentioned above and an additional check is performed in accordance with the rules of lossless assignments.

Examples:

"Leads to a data loss when converting to a data object accepting only a single character
TRY.
  DATA(exact1) = EXACT abap_bool( 'XY' ).
  CATCH CX_SY_CONVERSION_DATA_LOSS INTO DATA(error1).
ENDTRY.

"The calculation cannot be executed exactly; a rounding is necessary
TRY.
  DATA(exact2) = EXACT decfloat34( 1 / 3 ).
  CATCH CX_SY_CONVERSION_ROUNDING INTO DATA(error2).
ENDTRY.

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REF

The REF operator creates a data reference variable pointing to a specified data object.
The type specified after REF and directly before the first parenthesis determines the static type of the result.
The operator replaces GET REFERENCE and is particularly useful for avoiding the declaration of helper variables that are only necessary, for example, to specify data reference variables as actual parameters.
The following can be specified after REF before the first parenthesis: A non-generic data type that satisfies the rules of upcasts in data references, the generic type data, the # character if the type can be derived from the context.

Examples:

"Data references
"Declaring data object and assign value

DATA num TYPE i VALUE 5.

"Declaring data reference variable

DATA dref_a TYPE REF TO i.

"Getting references

dref_a = REF #( num ).

"Inline declaration and explicit type specification
DATA(dref_b) = REF string( `hallo` ).

"Object references

DATA(oref_a) = NEW some_class( ).

DATA(oref_b) = REF #( oref_a ).

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CAST

Using the CAST operator, you can carry out upcasts and downcasts and create a reference variable of a static type as a result.
It replaces the ?= operator and enables chained method calls.
The operator is particularly helpful for avoiding the declaration of helper variables and more contexts.
Similar to the NEW operator, constructor expressions with CAST can be followed by the object component selector -> to point to a class or interface attribute (... CAST class( ... )->attr) and methods (... CAST class( ... )->meth( ... )). Method chaining, standalone and functional method calls are possible, too. See more information here.

Run Time Type Identification (RTTI) examples:

"Getting component information
DATA(components) = CAST cl_abap_structdescr(
  cl_abap_typedescr=>describe_by_data( some_object ) )->components.

"Getting method information
DATA(methods) = CAST cl_abap_objectdescr(
  cl_abap_objectdescr=>describe_by_name( 'LOCAL_CLASS' ) )->methods.

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COND

The COND operator is used for either creating a result depending on logical expressions or raising a class-based exception (which is specified within the parentheses after the addition THROW).
There can be multiple logical expressions initiated by WHEN followed by the result specified after THEN. If none of the logical expressions are true, you can specify an ELSE clause at the end. If this clause is not specified, the result is the initial value of the specified or derived data type.
Note that all operands specified after THEN must be convertible to the specified or derived data type.

Example:

DATA(b) = COND #( WHEN a BETWEEN 1 AND 3 THEN w
                  WHEN a > 4 THEN x
                  WHEN a IS INITIAL THEN y
                  ELSE z ).

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SWITCH

The SWITCH operator is fairly similar to the COND operator and works in the style of CASE statements, i. e. it uses the value of only a single variable that is checked in the case distinction.

DATA(b) = SWITCH #( a
                    WHEN 1 THEN w
                    WHEN 2 THEN x
                    WHEN 3 THEN y
                    ELSE z ).

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FILTER

The FILTER operator constructs an internal table according to a specified type (which can be an explicitly specified, non-generic table type or the # character as a symbol for the operand type before the first parenthesis).
The lines for the new internal table are taken from an existing internal table based on conditions specified in a WHERE clause. Note that the table type of the existing internal table must be convertible to the specified target type.
The conditions can either be based on single values or a filter table.
Additions:

Addition	Details
`USING KEY`	Specifies the table key with which the `WHERE` condition is evaluated: either a sorted key or a hash key. If the internal table has neither of them, a secondary table key must be available for the internal table which must then be specified after `USING KEY`.
`EXCEPT`	The specification of `EXCEPT` means that those lines of the existing table are used that do not meet the condition specified in the `WHERE` clause. Hence, if `EXCEPT` is not specified, the lines of the existing table are used that meet the condition.

Examples:

"FILTER and conditions based on single values
"Assumption the component num is of type i.
DATA itab1 TYPE SORTED TABLE OF struc WITH NON-UNIQUE KEY num.
DATA itab2 TYPE STANDARD TABLE OF struc WITH NON-UNIQUE SORTED KEY sec_key COMPONENTS num.
DATA itab3 TYPE HASHED TABLE OF struc WITH UNIQUE KEY num.

"The lines meeting the condition are respected.
"Note: The source table must have at least one sorted or hashed key.
"Here, the primary key is used
DATA(f1) = FILTER #( itab1 WHERE num >= 3 ).

"USING KEY primary_key explicitly specified; same as above
DATA(f2) = FILTER #( itab1 USING KEY primary_key WHERE num >= 3 ).

"EXCEPT addition
DATA(f3) = FILTER #( itab1 EXCEPT WHERE num >= 3 ).
DATA(f4) = FILTER #( itab1 EXCEPT USING KEY primary_key WHERE num >= 3 ).

"Secondary table key specified after USING KEY
DATA(f5) = FILTER #( itab2 USING KEY sec_key WHERE num >= 4 ).
DATA(f6) = FILTER #( itab2 EXCEPT USING KEY sec_key WHERE num >= 3 ).

"Note: In case of a hash key, exactly one comparison expression for each key component is allowed;
"only = as comparison operator possible.
DATA(f7) = FILTER #( itab3 WHERE num = 3 ).

"Using a filter table
"In the WHERE condition, the columns of source and filter table are compared. Those lines in the source table
"are used for which at least one line in the filter table meets the condition. EXCEPT and USING KEY are also possible.

DATA filter_tab1 TYPE SORTED TABLE OF i
  WITH NON-UNIQUE KEY table_line.

DATA filter_tab2 TYPE STANDARD TABLE OF i
  WITH EMPTY KEY
  WITH UNIQUE SORTED KEY line COMPONENTS table_line.

DATA(f8) = FILTER #( itab1 IN filter_tab1 WHERE num = table_line ).

"EXCEPT addition
DATA(f9) = FILTER #( itab1 EXCEPT IN filter_tab1 WHERE num = table_line ).

"USING KEY is specified for the filter table
DATA(f10) = FILTER #( itab2 IN filter_tab2 USING KEY line WHERE num = table_line ).

"USING KEY is specified for the source table, including EXCEPT
DATA(f11) = FILTER #( itab2 USING KEY sec_key EXCEPT IN filter_tab2 WHERE num = table_line ).

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REDUCE

The REDUCE operator creates a result of a specified or derived type from one or more iteration expressions.
It basically reduces sets of data objects to a single data object. For example, the numeric values of a table column are summed up. As a result, the total number is constructed.

The following example calculates the total of the numbers from 1 to 10 using the REDUCE operator:

"sum: 55
DATA(sum) = REDUCE i( INIT s = 0
                      FOR  i = 1 UNTIL i > 10
                      NEXT s += i ) ).

💡 Note

INIT ...: A temporary variable is specified that sets an initial value for the result variable.

FOR ...: Represents a loop. The loop is carried out until the condition is met after UNTIL.

NEXT ...: Represents the assignment to the temporary variable after every iteration.

Once the loop has finished, the target variable is assigned the resulting value.

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Iteration Expressions with FOR

Using iteration expressions with the language element FOR, you can carry out conditional iterations (including the ABAP words UNTIL and WHILE which have the semantics of ABAP statements DO and WHILE) or table iterations (having the semantics of LOOP AT; the expressions include the ABAP word IN).
Such expressions are possible in the following contexts:
- REDUCE: The reduction result is created in the iteration steps.
- NEW and VALUE: Used in the context of looping across internal tables. New table lines are created in the iteration steps and inserted into a target table.

FOR ... WHILE: The following example with REDUCE has the same effect as the example using UNTIL shown above.

DATA(sum) = REDUCE i( INIT y = 0
                      FOR n = 1 THEN n + 1 WHILE n < 11
                      NEXT y += n ).

FOR ... UNTIL: See the example in the REDUCE section.

FOR ... IN:

The operand specified after FOR represents an iteration variable, i. e. a work area that contains the data while looping across the table.
This variable is only visible within the FOR expression, i. e. it cannot be used outside of the expression.
The type of the variable is determined by the type of the internal table specified after IN.
One or more iteration expressions can be specified using FOR.
The components or the whole table line that is to be returned are specified within the pair of parentheses before the closing parenthesis.
In contrast to LOOP statements, the sequential processing cannot be debugged.

Some examples for looping across tables and storing values in target tables:

"Looping across table and storing the whole line in a new table;
"the target table must have the same table type as the source table itab;
"without the WHERE condition, all lines are respected

TYPES t_type LIKE itab.

... = VALUE t_type( FOR wa IN itab
                    "WHERE ( comp1 > 2 )
                    ( wa ) ).

"Storing specific components having different names by specifying the assignment
"individually; assumption: the target type is not compatible to the type of itab;
"a field mapping is provided; pay attention to potential type conversion

... = VALUE t_type( FOR wa IN itab
                    "WHERE ( comp1 > 2 )
                    ( compX = wa-comp1
                      compY = wa-comp2 ) ).

"Storing specific components having the same names;
"assumption: Target type is not compatible to the type of itab;
"if there are identically named components in the table types, you might
"also use CORRESPONDING

... = VALUE t_type( FOR wa IN itab
                    "WHERE ( comp1 > 2 )
                    ( CORRESPONDING #( wa ) ) ).

"Multiple iteration expressions

... = VALUE t_type( FOR wa1 IN itab1 WHERE ( comp1 = 4 )
                    FOR wa2 IN itab2 WHERE ( comp2 > 5 )
                    FOR wa3 IN itab3 WHERE ( comp3 < 3 )
                    ( compX = wa1-comp1
                      compY = wa2-comp2
                      compZ = wa3-comp3 ) ).

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LET Expressions

LET expressions allow you to declare local helper fields (variables or fields symbols) and assign values (the type is derived from the defined value) to be used in constructor expressions, for example, in iteration expressions using FOR or results specified in the conditional expressions of COND and SWITCH.
Note that the helper field is only valid in the context in which the LET expression is specified.

Examples:

"Creating a string table using a LET expression

DATA(str_tab) = VALUE string_table( LET it = `be` IN
                    ( |To { it } is to do| )
                    ( |To { it } or not to { it }| )
                    ( |To do is to { it }| )
                    ( |Do { it } do { it } do| ) ).

"Conditional expressions

DATA(a) = COND #( LET b = c IN
                  WHEN b > x THEN ...
                  WHEN b < y THEN ...
                  ...
                  ELSE ... ).

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Executable Example

zcl_demo_abap_constructor_expr

Note the steps outlined here about how to import and run the code.

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05_Constructor_Expressions.md

05_Constructor_Expressions.md

Constructor Expressions

Introduction

VALUE

CORRESPONDING

NEW

CONV

EXACT

REF

CAST

COND

SWITCH

FILTER

REDUCE

Iteration Expressions with FOR

LET Expressions

Executable Example

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05_Constructor_Expressions.md

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Constructor Expressions

Introduction

VALUE

CORRESPONDING

NEW

CONV

EXACT

REF

CAST

COND

SWITCH

FILTER

REDUCE

Iteration Expressions with FOR

LET Expressions

Executable Example