6.2.24.1 "COBOL Language Reference" IBM Library Server

6.2.24.1 Elementary Moves

An elementary move is one in which the receiving item is an elementary item, and the sending item is an elementary item or a literal. Any necessary conversion of data from one form of internal representation to another takes place during the move, along with any specified editing in, or de-editing implied by, the receiving item. Each elementary item belongs to one of the following categories:

Alphabetic--includes alphabetic data items and the figurative constant SPACE.
Alphanumeric--includes alphanumeric data items, nonnumeric literals, and all figurative constants except SPACE and ZERO (when ZERO is moved to a numeric or numeric-edited item).
Alphanumeric-Edited--includes alphanumeric-edited data items.
Numeric--includes numeric data items, numeric literals, and the figurative constant ZERO (when ZERO is moved to a numeric or numeric-edited item).
Numeric-Edited--includes numeric-edited data items.
X Floating-point--includes internal floating-point items (defined as
X USAGE COMP-1 or USAGE COMP-2), external floating-point items (defined
X as USAGE DISPLAY), and floating-point literals.
X DBCS--includes DBCS data items (defined explicitly or implicitly as
X USAGE DISPLAY-1) and DBCS literals.

The following rules outline the execution of valid elementary moves. When the receiving field is:

Alphabetic:

Alignment and any necessary space filling occur as described under "Alignment Rules" in topic 5.1.6.6.
If the size of the sending item is greater than the size of the receiving item, excess characters on the right are truncated after the receiving item is filled.

Alphanumeric or Alphanumeric-Edited:

Alignment and any necessary space filling take place, as described under "Alignment Rules" in topic 5.1.6.6.
If the size of the sending item is greater than the size of the receiving item, excess characters on the right are truncated after the receiving item is filled.
If the sending item has an operational sign, the unsigned value is used. If the operational sign occupies a separate character, that character is not moved, and the size of the sending item is considered to be one less character than the actual size.

Numeric or Numeric-edited:

Except where zeros are replaced because of editing requirements, alignment by decimal point and any necessary zero filling take place, as described under "Alignment Rules" in topic 5.1.6.6.
If the receiving item is signed, the sign of the sending item is placed in the receiving item, with any necessary sign conversion. If the sending item is unsigned, a positive operational sign is generated for the receiving item.
If the receiving item is unsigned, the absolute value of the sending item is moved, and no operational sign is generated for the receiving item.
When the sending item is alphanumeric, the data is moved as if the sending item were described as an unsigned integer.
X When the sending item is floating-point, the data is first converted
X to either a binary or internal decimal representation and is then
X moved.
De-editing allows moving a numeric-edited data item into a numeric or numeric-edited receiver. The compiler accomplishes this by first establishing the unedited value of the numeric-edited item (this value can be signed), then moving the unedited numeric value to the receiving numeric or numeric-edited data item.

X Floating-point:

X The sending item is converted first to internal floating-point and
X then moved.
X When data is moved to or from an external floating-point item, the
X data is converted first to or from its equivalent internal
X floating-point value.

X DBCS:

X No conversion takes place.
X If the sending and receiving items are not the same size, the data
X item will be either truncated or padded with DBCS spaces on the right.
X >_Workstation_> Under AIX, OS/2, and Windows, if the padding required
X is not in a multiple consistent with double-byte characters,
X single-byte characters will be used (for example, a group item moved
X to a DBCS data item). <_Workstation_<

Notes:

1. If the receiving field is alphanumeric or numeric-edited, and the sending field is a scaled integer (that is, has a P as the rightmost character in its PICTURE character-string), the scaling positions are treated as trailing zeros when the MOVE statement is executed.

2. If the receiving field is numeric and the sending field is alphanumeric literal or ALL literal, then all characters of the literal must be numeric characters.

Table 42 shows valid and invalid elementary moves for each category. In the table:

YES = Move is valid.
NO = Move is invalid.

X X Sending Item X Category	X X Alpha- X betic	X X Alpha- X numeric	X Alpha- X numeric X Edited	X X X Numeric	X X X Numeric-	X External X Floating X dPoint	X Internal X Floating X Point	X X X DBCS(1)

Table 42. Valid and Invalid Elementary Moves
X X Sending Item X Category	Receiving Item Category
Alphabetic and X SPACE	X Yes	X Yes	X Yes	X No	X No	X No	X No	X No
X Alphanumeric(2)	X Yes	X Yes	X Yes	X Yes (3)	X Yes (3)	X Yes(8)	X Yes(8)	X No
X Alphanumeric-Edi	X ed Yes	X Yes	X Yes	X No	X No	X No	X No	X No
Numeric Integer X and ZERO(4)	X No	X Yes	X Yes	X Yes	X Yes	X Yes	X Yes	X No
Numeric X Non-integer(5)	X No	X No	X No	X Yes	X Yes	X Yes	X Yes	X No
X Numeric-Edited	X No	X Yes	X Yes	X Yes	X Yes	X Yes	X Yes	X No
X Floating X point(6)	X X No	X X No	X X No	X X Yes	X X Yes	X X Yes	X X Yes	X X No
X DBCS(7)	X No	X No	X No	X No	X No	X No	X No	X Yes
Note: X (1) Includes DBCS data items. (2) Includes nonnumeric literals. X (3) Figurative constants and nonnumeric literals must consist only of numeric characters and X will be treated as numeric integer fields. (4) Includes integer numeric literals. (5) Includes non-integer numeric literals. X (6) Includes floating-point literals, external floating-point data items (USAGE DISPLAY), and X internal floating-point data items (USAGE COMP-1 or USAGE COMP-2). X (7) Includes DBCS data-items, DBCS literals, and SPACE. (8) Figurative constants and nonnumeric literals must consist only of numeric characters and will be treated as numeric integer fields. The ALL literal cannot be used as a sending item.

Subtopics:

6.2.24.1.1 Moves Involving Date Fields

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6.2.24.1 Elementary Moves

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