Terms used to describe actions

Expression


Expression is a sequence of characters, which form a correct mathematic expression. If it is required, that an expression should get a value of a particular type, then this value type will be identified as follows:

  • Boolean - Bo
  • Integer - Int
  • Real - Re
  • Absolute time - AbsTime
  • Time interval (relative time) - RelTime
  • Text - Txt
  • HBJ - Hbj

Identifier of value


Identifier of value (see also Identifiers) is:

  • object name
  • local variable name
  • directly written variable. There are 3 admissible types 
    • text constant (e.g.: "This is a text constant")
    • integer constant (standard declaration of an integer number)
    • real constant (declaration of a real number. e.g.: 3.14159)
    • system constant (@TRUE, @Run, ...)

In case that the name of an object identifies an object of Structured variable, then access to the item (optionally an index) must follow the name. For example:

SV.Structure^Int
SV.Structure[2]^Int

Similarly, if a local variable is of RECORD type or type ALIAS, then access to the item (optionally an index) must necessarily follow the name. For example:

RECORD (SD.RecordDef) _locRecord
ALIAS  (SD.RecordDef) _aliasRecord
INT    _index

_locRecord[_index]^Int
_aliasRecord^Int

As we can see from the examples, the index (row number) is enclosed in square brackets []. Index, in the declaration, is evaluated as an expression, which has to get a value of Int type.

According to the identifier definition, the following types belong into this category::
IC_C, IC_O, IC_O_R_RIA, IC_O_R_RIN, IC_L, IC_L_CONST, IC_L_AN, IC_L_AT_RIA, IC_L_AT_RIN, IC_L_RNA_RIA, IC_L_RNA_RIN, IC_L_R_RIA, IC_L_R_RIN.

Identifier of structure row


The identifier of a structure row is:

  • indexed name of an object of Structured variable type
  • indexed name of a local variable of RECORD type or type ALIAS

An example for objects:

INT _index

SV.Structure[_index+1]
SV.Structure[1]

An example for local variable:

RECORD (SD.RecordDef) _locRecord
ALIAS  (SD.RecordDef) _aliasRecord
INT    _index

_locRecord[3]
_locRecord[_index]

_aliasRecord[_index]
_aliasRecord[6]

According to the identifier's definition, the following types belong to this category:
IC_O_R_R, IC_L_AT_R, IC_L_RNA_R, IC_L_R_R, and the index placed after identifier must be <> 0.

Identifier of structure column


A structure column is identified by its name. Therefore, structure column identifier can be defined in two ways:

  • SV.StructureName[...]^ColumnName - in case of the object of Structured variable type
  • _locRecord[...]^ColumnName - in case of a local variable of RECORD type

The structure row index is not important.

Identifier of structure item


A structure item is identified by its name. Therefore, structure item identifier can be defined in two ways:

Identifier of the entire structure


Identifier of the entire structure is:

  • name of an object of Structured variable type
  • name of a local variable of RECORD type or types ALIAS

An example for objects:

INT _index

SV.Structure

An example for local variable:

RECORD (SD.RecordDef) _locRecord
ALIAS  (SD.RecordDef) _aliasRecord
INT    _index

_locRecord
_aliasRecord

According to the identifier's definition, the following types belong to this category:
IC_O_R, IC_O_R_R*, IC_L_AT_R*, IC_L_RNA, IC_L_RNA_R*, IC_L_R, IC_L_R_R*

* index behind an identifier must be = 0.

Reference to object


Reference to object is a special case of value identifier, where its value must the reference to an object or the identifier is directly the object itself.

For example:

; the object itself is a reference
Sec
SysTime
U.Int

; Structure item
SV.Struktura[_index]^Object
RECORD (SD.RecordDef) _rec
_rec[_index]^Object

; Alias is the reference to the object
ALIAS _a
_a

According to the identifier's definition, the following types belong to this category:
IC_O, IC_O_R, IC_O_R_RIA, IC_L_AN, IC_L_AT, IC_L_AT_RIA, IC_L_R_RIA.

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