| Object COBOL Language Extensions |
|
Syntax Summary for COBOL Features | |
Compiler-directing statements control the processing of a compilation
group. The following compiler-directing facilities are provided:
Source text manipulation allows you to specify text that is to be copied
from a source user-library. This is usually created using any suitable
source text editor.
It also allows you to replace source text as part of
the compilation of a compilation group.
COBOL libraries consist of files that contain source to be made
available to the COBOL system. The effect of the interpretation of the
COPY statement is to insert text into the compilation group, where it will
be treated by the COBOL system as part of the compilation group. All
occurrences of a given literal, identifier, word or group of words in the
library text can be replaced with alternative text during the copy
process. Source text manipulation also allows you to access more than one
COBOL library at the time the object code is created.
The effect of the REPLACE statement is to
substitute new text for text appearing in the source text and have the new
text treated by your COBOL system as part of the source text.
Function
The COPY statement incorporates text into a COBOL compilation group .
Examples
- An example of using the OLDCOPY Compiler directive to achieve ANSI'68
or LANGLVL(1) behavior is provided in the Examples chapter in
your Language Reference - Additional Topics.
- An example of using the COPY statement with partial word replacement
supported by ANSI'85 rules is provided in the Examples chapter
in your Language Reference - Additonal Topics.
General Format
Directives
- In addition to Compiler directives which provide flagging and modify
the reserved word list, the following directives may impact either the
syntax or semantics described in this section.
- COPYEXT - specifies the filename extension to be used for
locating copy files.
- COPYLBR - specifies that library-names are equivalent to .lbr
files.
- COPYLIST - causes the result of a copy statement to be included
in the listing file.
- FOLD-COPY-NAME - allows the compile system to find a copy library
member when the library name on disk and the text-name in the COPY
statement do not use the same upper-case and lower-case letters for
the library member name.
- OLDCOPY - changes the handling of COPY statements to match the
ANS'68 and OS/VS COBOL LANGLVL(1) rules.
Syntax Rules
- If more than one COBOL library is available while the source is
passed through the COBOL system, text-name must be qualified by the
library-name identifying the COBOL library in which the text associated
with text-name resides. See your COBOL system documentation for details
of libraries.
This restriction is removed.
- The
COPY statement must be preceded by a space and terminated by the
separator period.
-
Pseudo-text-1 must not be null, nor can it consist solely of
either the character space(s) or comment lines.
- Pseudo-text-2 can be null.
- Character-strings within pseudo-text-1 and pseudo-text-2 can be
continued. However, both characters of a pseudo-text delimiter must be
on the same line. (See the section Continuation of Lines in the
chapter Concepts of a COBOL Compilation Group.)
- Word-1 or word-2 can be any single COBOL word.
- A COPY statement can occur in the compilation group anywhere a
character-string or a separator can occur except that a COPY statement
must not occur within another COPY statement.
- Text-name defines a unique external file-name which conforms to the
rules for user defined words.
External-file-name-literal is an alphanumeric
literal that conforms to the operating system rules for file-names. It
can be specified with or without enclosing quotation marks.
Text-names and unquoted external-file-name-literals are always
converted to uppercase.
-
Library-name-literal is an alphanumeric literal
that conforms either to the operating system rules for file-names or to
the operating system rules for device identifiers. It can be specified
with or without enclosing quotation marks.
Unquoted library-name-literals are always converted to uppercase.
-
The SUPPRESS phrase is used to suppress printing
the contents of the copy member on the source listing.
-
If the word COPY appears in a comment-entry or in
the place where a comment entry can appear, it is considered part of the
comment-entry.
A COPY statement that appears in a comment-entry
is processed.
-
External-file-name-literal and
library-name-literal, when enclosed in quotation marks, may contain the
$, #, and @ characters.
General Rules
- The compilation of a compilation group containing
COPY statements is logically equivalent to processing all COPY
statements prior to the processing of the resultant compilation group.
- The effect of processing a COPY statement is that the library text
associated with text-name is copied into the source text, logically
replacing the entire COPY statement, beginning with the reserved word
COPY and ending with the punctuation character period, inclusive.
- If the REPLACING phrase is not specified, the library text is copied
unchanged.
If the REPLACING phrase is specified, the library text is copied and
each properly matched occurrence of pseudo-text-1, identifier-1,
literal-1 and word-1 in the library text is replaced by the
corresponding pseudo-text-2, identifier-2, literal-2 or word-2.
- For purposes of matching, identifier-1, literal-1 and word-1 are
treated as pseudo-text containing only identifier-1, literal-1 or
word-1, respectively.
- The comparison operation to determine text replacement occurs in the
following manner:
- The leftmost library text word which is not a separator comma or
a separator semicolon is the first text word used for comparison.
Any text word or space preceding this text word is copied into the
source text. Starting with the first text word for comparison and
first pseudo-text-1, identifier-1, word-1, or literal-1 that was
specified in the REPLACING phrase, the entire REPLACING phrase
operand that precedes the reserved word BY is compared to an
equivalent number of contiguous library text words.
- Pseudo-text-1, identifier-1, word-1, or literal-1 match the
library text if, and only if, the ordered sequence of text words
that forms pseudo-text-1, identifier-1, word-1, or literal-1 is
equal, character for character, to the ordered sequence of library
text words. For purposes of matching, each occurrence of a separator
comma, semicolon, or space in pseudo-text-1 or in the library text
is considered to be a single space. Each sequence of one or more
space separators is considered to be a single space.
Each lowercase letter is equivalent to the
corresponding uppercase letter as specified for the COBOL
character set.
- If no match occurs, the comparison is repeated with each next
successive pseudo-text-1, identifier-1, word-1, or literal-1, if
any, in the
REPLACING phrase until either a match is found or there is
no next successive REPLACING operand.
- When all the REPLACING phrase operands have been compared and no
match has occurred, the leftmost library text word is copied into
the source text. The next successive library text word is then
considered as the leftmost library text word, and the comparison
cycle starts again with the first pseudo-text-1, identifier-1,
word-1, or literal-1 specified in the REPLACING phrase.
- Whenever a match occurs between pseudo-text-1, identifier-1,
word-1, or literal-1 and the library text, the corresponding
pseudo-text-2, identifier-2, word-2, or literal-2 is placed into the
source text. The library text word immediately following the
rightmost text word that participated in the match is then
considered as the leftmost text word. The comparison cycle starts
again with the first pseudo-text-1, identifier-1, word-1, or
literal-1 specified in the REPLACING phrase.
- The comparison operation continues until the rightmost text word
in the library text has either participated in a match or been
considered as a leftmost library text word and participated in a
complete comparison cycle.
- A comment line occurring in either the library text or pseudo-text-1
is interpreted, for purposes of matching, as a single space. Comment
lines appearing in either pseudo-text-2 or library text are copied into
the source text unchanged.
- Debugging lines are permitted within library text and pseudo-text-2.
Debugging lines are not permitted within pseudo-text-1; text-words
within a debugging line participate in the matching rules as if the "D"
did not appear in the indicator area.
A debugging line is specified within pseudo-text
if the debugging line begins in the source text after the opening
pseudo-text delimiter but before the matching closing pseudo-text
delimiter.
- The text produced as a result of the complete processing of a COPY
statement must not contain a
COPY statement.
This text can contain a COPY statement provided
neither this contained COPY nor the already expanded COPY includes the
REPLACING phrase. However, recursive COPY statements (where a
library-text is referred to by a COPY statement within it) are not
allowed.
COPY statements may be nested in this way to any
level. One of the COPY statements in this structure may include the
REPLACING phrase, and the replacements specified will be in effect for
all subsidiary COPY statements.
- The syntactic correctness of the library text cannot be independently
determined.
Except for COPY statements,
the syntactic correctness of the entire COBOL compilation group
cannot be determined until all COPY statements have been completely
processed.
- Each text word copied from the library but not replaced is copied so
as to start in the same area of the line in the resultant source text as
it begins in the line within the library. However, if a text word copied
from the library begins in area A but follows another text word, which
also begins in area A of the same line, and if replacement of a
preceding text word in the line by replacement text of greater length
occurs, the following text word begins in area B if it cannot begin in
area A. Each text word in pseudo-text-2 that is to be placed into the
resultant source text begins in the same area of the resultant source
text as it appears in pseudo-text-2. Each identifier-2, literal-2, and
word-2 that is to be placed into the resultant source text begins in the
same area of the resultant source text as the leftmost library text word
that participated in the match would appear if it had not been replaced.
Library text must conform to the rules for COBOL reference format.
If additional lines are introduced into the source text as a result
of a COPY statement, each text word introduced appears on a debugging
line if the copy statement begins on a debugging line, or if the text
word being introduced appears on a debugging line in library text.
When a text word specified in the BY phrase is introduced, it appears
on a debugging line if the first library text word being replaced is
specified on a debugging line. Except in the preceding cases, only
those text words that are specified on debugging lines where the
debugging line is within pseudo-text-2 appear on debugging lines in
the resultant source text. If any literal specified as literal-2 or
within pseudo-text-2 or library text is of too great a length to be
accommodated on a single line without continuation to another line in
the resultant source text and the literal is not being placed on a
debugging line, additional continuation lines are introduced which
contain the remainder of the literal. If replacement requires that the
continued literal be continued on a debugging line, the compilation
group is in error.
- For purposes of compilation, text-words after replacement are placed
in the source text according to the rules for reference format as
described in the chapter Concepts of a COBOL Program.
- If the unit identifier is not explicitly specified, the default drive
will be used. (The default is operating system-dependent.)
-
The OLDCOPY Compiler directive causes the entire
entry to be replaced by the information identified by text-name, except
that the data-name preceding the
COPY statement replaces the corresponding data-name in the
text-name.
-
If certain conventions are followed in library
text, parts of names, for example the prefix portion of data-names, can
be changed with the REPLACING phrase.
To use this type of "partial word
replacement" the portion of the words to be modified must be
enclosed as follows:
- In pairs of left and right parentheses. For example, (ABC)
- Within colons. For example :XYZ: is a valid candidate.
Function
The REPLACE statement is used to replace source text in a compilation
unit.
General Formats
Format 1
Format 2
Syntax Rules
- A REPLACE statement can occur wherever a character-string can occur
in the compilation group. It must be preceded by a separator period
except when it is the first statement in a compilation group.
- A REPLACE statement must be terminated by a separator period.
-
Pseudo-text-1 must contain one or more text words.
- Pseudo-text-2 can contain zero, one, or more text words.
- Character-strings within pseudo-text-1 and pseudo-text-2 can be
continued.
- A text word within pseudo-text must be between 1 and 322 characters
long.
- Pseudo-text-1 must not consist entirely of a separator comma or a
separator semicolon.
- If the word REPLACE appears in a comment-entry or in the place where
a comment-entry can appear, it is considered part of the comment-entry.
General Rules
- Pseudo-text-1 specifies the source text to be replaced by
pseudo-text-2.
- The Format 2 REPLACE statement specifies that any text replacement
currently in effect is discontinued.
- A given occurrence of the
REPLACE statement is in effect from the point at which it is
specified until the next occurrence of the statement or the end of the
compilation unit, respectively.
- Any REPLACE statements contained in a source unit are processed after
the processing of any COPY statements contained in that source unit..
- The text produced as a result of the processing of a REPLACE
statement must contain neither a COPY statement nor a REPLACE statement.
- The comparison operation to determine text replacement occurs in the
following manner:
- Starting with the leftmost source text word and the first
pseudo-text-1, pseudo-text-1 is compared to an equivalent number of
contiguous source text words.
- Pseudo-text-1 matches the source text if, and only if, the order
sequence of text words that forms pseudo-text-1 is equal, character
for character, to the ordered sequence of source text words. For
purposes of matching, each occurrence of a separator comma,
semicolon, or space in pseudo-text-1 or in the source text is
considered to be a single space. Each sequence of one or more space
separators is considered to be a single space.
Each lowercase letter is equivalent to the corresponding
uppercase letter as specified for the COBOL character set.
- If no match occurs, the comparison is repeated with each next
successive occurrence of pseudo-text-1, until either a match is
found or there is no next successive occurrence of pseudo-text-1.
- Whenever a match occurs between pseudo-text-1 and the source
text, the corresponding pseudo-text-2 replaces the matched text in
the source text. The source text word immediately following the
rightmost text word that participated in the match is then
considered as the leftmost source text word. The comparison cycle
starts again with the first occurrence of pseudo-text-1.
- The comparison operation continues until the rightmost text word
in the source text which is within the scope of the REP
LACE statement has either participated in a match or been
considered as a leftmost source text word and participated in a
complete comparison cycle.
- Comment lines or blank lines occurring in either the source text or
pseudo-text-1 are ignored for purposes of matching; and the sequence of
text words in the source text and in pseudo-text-1 is determined by the
rules for reference format. See the section Reference Format
Representation in the chapter Concepts of a COBOL Program.
Comment lines or blank lines in pseudo-text-2 are placed into the
resultant source text unchanged whenever pseudo-text-2 is placed into
the source text as a result of text replacement. A comment line or blank
line in source text is not placed into the resultant source text if that
comment line or blank line appears within the sequence of text words
that match pseudo-text-1.
- Debugging lines are permitted in pseudo-text. Text words within a
debugging line participate in the matching rules as if the "D"
did not appear in the indicator area.
- Only after all COPY and REPLACE statements have been completely
processed, can the syntactical correctness of the rest of the source
code be determined.
- Text words inserted into the source text as a result of processing a
REPLACE statement are placed in the source text according to the rules
for reference format. See the section Reference Format in the
chapter Concepts of a COBOL Program. When inserting text words
of pseudo-text-2 into the source text, additional spaces can be
introduced only between text words where a space (including the assumed
space between source lines) already exists.
- If additional lines are introduced into the source text as a result
of the processing of REPLACE statements, the indicator area of the
introduced lines contains the same character as the line on which the
text being replaced begins, unless that line contains a hyphen, in which
case the introduced line contains a space.
If any literal within pseudo-text-2 is of a length too great to be
accommodated on a single line without continuation to another line in
the resultant source text and the literal is not being placed on a
debugging line, additional continuation lines are introduced to
contain the remainder of the literal. If replacement requires the
continued literal to be continued on a debugging line, the compilation
unit is in error.
A compiler directive specifies options or compilation variables for use
by the compiler.
General Format
>>compiler-instruction
Syntax Rules
- A compiler directive must be specified on one line, except for the
EVALUATE and the IF directives for which specific rules are specified.
- A compiler directive must be preceded only by zero, one, or more
space characters.
- When the reference format is fixed format, a compiler directive shall
be specified in the program-text area and may be followed only by space
characters.
- When the reference format is free form, a compiler directive can be
followed only by space characters and an optional in-line comment.
- A compiler directive is composed of the two contiguous COBOL
characters >>, optionally followed by the COBOL character space,
followed by compiler-instruction. >> shall be treated as though it
were followed by a space if no space is specified after >>.
- Compiler-instruction is composed of the compiler-directive words
defined in the specific syntax for each directive.
- A compiler-directive word is reserved within the context of the
compiler directive in which it is specified and may be used elsewhere as
any type of COBOL word.
- A compiler directive can be specified anywhere in a compilation group
except
- as restricted by the rules for the specific compiler directive,
- within a source text manipulation statement,
- between the lines of a continued character string,
- on a debugging line.
- Compiler directive lines can be specified within library text.
- A literal in a compiler directive must not be specified as a
concatenation expression or a figurative constant.
General Rules
- A compiler directive is treated as a single blank line during the
matching operation of a COPY or REPLACE statement. A directive will not
match any pseudo-text or partial-word and therefore will not be affected
by the replacing action.
- A compiler directive is processed before, during, or after the
processing of COPY and REPLACE statements as indicated in the specific
rules for each directive.
- The compiler directives >>EVALUATE, and >>IF, when
specified in the source-text of >>IF and >>EVALUATE
directives shall take effect when encountered during conditional
compilation. All other compiler directives are processed when the source
code resulting from conditional compilation is processed.
The use of certain compiler directives provides a means of including or
omitting selected lines of source code. This is called conditional
compilation. The compiler directives that are used for conditional
compilation are the EVALUATE directive and the IF directive. The EVALUATE
and IF directives are used to select lines of code that are to be compiled
or are to be omitted during compilation.
An arithmetic expression can be specified in the EVALUATE directive and
in a constant conditional expression. The formation, the order of
precedence, and the rules for evaluation of these arithmetic expressions
are shown in
Arithmetic Expressions in the chapter Procedure
Division. The following addition rules apply:
- All operands must be fixed-point numeric literals or arithmetic
expressions in which all operands are fixed-point numeric literals.
Note: This includes constants that are equated to a
fixed-point numeric literal.
- After each arithmetic operation, the result is truncated to the
integer part of the value and the resultant value is considered to be an
integer.
- After the arithmetic expression is evaluated, the resulting value is
considered to be a numeric literal.
- An arithmetic expression must not result in a size error condition.
A constant conditional expression is a conditional expression in which
all the operands are literals or arithmetic expressions containing only
literal terms. A special form of condition known as a defined condition
may also be used as part of a constant conditional expression.
Syntax Rules
- A constant conditional expression must be one of the following:
- A simple relation condition in which both operands are either
literals or arithmetic expressions containing only literal terms and
which is formed according to the rules in
Relation Condition in the chapter Procedure
Division. The following rules also apply:
- The operands on both sides of the relational operator must be
the same category. An arithmetic expression is of the category
numeric.
- If literals are specified and they are not numeric literals,
the relational operator must be "IS [ NOT ] EQUAL TO"
or "IS [ NOT ] =".
- A defined condition.
- A complex condition as specified in
Complex Conditions in the chapter Procedure
Division is formed by combining the above forms of simple
conditions into complex conditions. Abbreviated combined relation
conditions must not be specified.
General Rules
- Complex conditions are evaluated according to the rules in
Complex Conditions in the chapter Procedure Division.
- For a simple relation condition where the operands are not numeric,
no collating sequence is used for the comparison. A character by
character comparison for equality is used.
Note: This means that uppercase and lowercase letters are not
equivalent.
General format
compilation-variable-name-1 IS [ NOT ] DEFINED
General Rules
- A defined condition using the IS DEFINED syntax evaluates TRUE if
compilation-variable-name-1 is currently defined.
- A defined condition using the IS NOT DEFINED syntax evaluates TRUE if
compilation-variable-name-1 is not currently defined.
The EVALUATE directive provides for multi-branch conditional
compilation.
General Format
Format 1
Format 2
Syntax Rules
All Formats
- Each pair of contiguous COBOL characters >> and the succeeding
compiler-directive words and operands up to, but not including,
source-text-1 and source-text-2 must be specified on a new line and be
specified entirely on that line. The first text-word of source-text-1
and the first text-word of source-text-2 must each begin on a new line.
- Source-text-1 and source-text-2 can be any kind of source text,
including compiler directives. Source-text-1 and source-text-2 can span
multiple lines.
Format 1
- All operands of one EVALUATE directive must be of the same category.
For this rule, an arithmetic expression is of category numeric.
- If the THROUGH phrase is specified, all selection subjects and
selection objects must be of category numeric.
- The words THROUGH and THRU are equivalent.
General Rules
All Formats
- The EVALUATE directive is processed during the processing of COPY and
REPLACE statements.
Format 1
- Literal-1 or arithmetic-expression-1, referred to as the selection
subject, is compared against the values specified in each WHEN phrase in
turn as follows:
- If the THROUGH phrase is not specified, a TRUE result is returned
if the selection subject is equal to literal-2 or
arithmetic-expression-2.
- If the THROUGH phrase is specified, a TRUE result is returned if
the selection subject lies in the inclusive range determined by
literal-2 or arithmetic-expression-2 and literal-3 or
arithmetic-expression-3.
As soon as a WHEN phrase is found that yields a TRUE result, the
associated source-text-1 is compiled and all remaining lines up to and
including the >>END-EVALUATE line are ignored. If no WHEN phrase
yields a TRUE result, the source-text-2 associated with the >>WHEN
OTHER phrase, if specified, is compiled.
Format 2
- For each WHEN phrase in turn, the constant-conditional-expression is
evaluated.
As soon as a WHEN phrase is found that yields a TRUE result, the
associated source-text-1 is compiled and all remaining lines up to and
including the >>END-EVALUATE line are ignored. If no WHEN phrase
yields a TRUE result, the source-text-2 associated with the >>WHEN
OTHER, if specified, is compiled.
The IF directive provides for 1 or 2-way conditional compilation.
General Format
>>IF constant-conditional-expression-1 [source-text-1]
[ >>ELSE [source-text-2] ]
>>END-IF
Syntax Rules
- Each pair of contiguous COBOL characters >> and the succeeding
compiler-directive words and operands up to, but not including,
source-text-1 and source-text-2 must be specified on a new line and be
specified entirely on that line. The first text-word of source-text-1
and the first text-word of source-text-2 must each begin on a new line.
- Source-text-1 and source-text-2 may be any kind of source text,
including compiler directives. Source-text-1 and source-text-2 may span
multiple lines.
General Rules
- The IF directive is processed during the processing of COPY and
REPLACE statements.
- If constant-conditional-expression-1 evaluates to TRUE, then
source-text-1 is compiled as part of the source text, and source-text-2
is ignored.
- If constant-conditional-expression-1 evaluates to FALSE, then
source-text-1 is ignored and source-text-2, if specified, is compiled as
part of the source text.
The REPOSITORY directive specifies whether information is added to the
external repository. It also specifies whether prototypes and definitions
are checked against the interface information in the external repository.
General Format
Directives
- In addition to the Compiler directives which provide flagging and
modify the reserved word list, the following directives may impact
either the syntax or semantics described in this section.
- RDFPATH - specifies the location of the library for the
repository files.
Syntax Rules
- The REPOSITORY directive must be specified only before the first
identification division of a compilation unit and must not be specified
within a compilation unit.
- The REPOSITORY directive applies to the remainder of the compilation
group or until another REPOSITORY directive is encountered.
General Rules
- The default REPOSITORY directive is:
>>REPOSITORY UPDATE OFF WITH CHECKING.
- If the ON phrase is specified explicitly or implicitly, the
information for a compilation unit is added to the external repository
before the next compilation unit is compiled or at the end of the
compilation group if there is no next compilation unit.
- If the OFF phrase is specified, the external repository is not
updated by the compiler.
- If the CHECKING phrase is specified, a warning mechanism flags a
class-definition or interface-definition that differs from the
information about that source unit in the external repository. Details
on the information in the external repository are specified in
External Repositoryin the chapter Concepts of a
Compilation Group .
The Basis mechanism provides support to allow an entire COBOL source
file to be noninteractively edited (temporarily) and the result of this
edit to be submitted to your COBOL system. The COBOL source file
referenced as the source of the temporary edit (the "subject-program")
remains unchanged, and there is no record of the result of the edit other
than the files output by your COBOL system (listing, and so on). The
resulting code file cannot be animated since there is no source file for
reference.
The BASIS mechanism is valid for fixed format source only.
The program submitted to your COBOL system consists of two files: an
edit control file (containing the BASIS statement and editing information)
and the COBOL source file (the "subject program" as described
above).
Three special statements are associated with the BASIS mechanism:
- BASIS
- INSERT
- DELETE.
These special statements are not part of the COBOL language. They must,
in their entirety, be contained on a single line and must be in upper
case.
If you modify the COBOL source program provided by a BASIS statement
with INSERT or DELETE statements, the sequence field of the COBOL source
program must contain numeric sequence numbers in ascending order.
General Notes on Basis Mechanism Statements
- DELETE statements wholly within area B of the source-program line,
not followed by a valid subject-sequence or subject-sequence-range, will
be treated as a COBOL DELETE statement by your COBOL system.
- Within the Basis mechanism DELETE statement, all subject-sequence and
subject-sequence-range numbers must be in ascending numeric order.
- Within the edit control file, all subject-sequence and
subject-sequence-range numbers must be in ascending numeric order.
Function
The BASIS statement identifies that the program (the edit control file
and the COBOL source file) is to be submitted to your COBOL system under
the BASIS mechanism rules.
General Format
Syntax Rules
- The BASIS statement must be the first line of the edit control file.
- The BASIS reserved word can commence anywhere between columns 1 and
66 of the statement line.
- Sequence numbers can be included anywhere in columns 1 through 6 of
the statement and must be followed by a space.
- Text-name defines a unique external file-name which conforms to the
rules for user defined words (note lower case is translated into upper
case). External-file-name-literal is an alphanumeric literal enclosed in
quotation marks, which conforms to the operating system rules for
file-names.
General Rules
- Text-name or external-file-name-literal determines the COBOL source
file to be edited by the control file.
- The editing of the COBOL source file is determined by the INSERT and
DELETE statements in the edit control file.
Function
The DELETE statement (under the Basis mechanism) identifies lines of the
COBOL source file to be ignored by your COBOL system. Any COBOL statements
that follow the DELETE statement (up to the next Basis-mechanism INSERT or
DELETE statement in the edit control file) are included.
General Format
Syntax Rules
- The DELETE reserved word can commence anywhere between columns 1 and
66 of the statement line.
- Sequence numbers can be included anywhere in columns 1 through 6 of
the statement and must be followed by a space.
- Subject-sequence-1, subject-sequence-2, and so on, must be unquoted
6-digit positive integers (following the rules for integer
numeric-literals).
- Subject-sequence-range-1, subject-sequence-range-2, and so on, must
consist of two subject-sequence numbers (as above) separated by a hyphen
(-).
- The comma between subject-sequences and/or subject-sequence ranges is
mandatory.
General Rules
- Subject-sequence-1, subject-sequence-2, and so on, refer to sequence
numbers of those statements within the COBOL source file which are to be
ignored by your COBOL system.
- Subject-sequence-range-1, subject-sequence-range-2, and so on, refer
to inclusive ranges of statement sequence numbers within the COBOL
source file, all of which statements are to be ignored when the
intermediate code is produced.
- Any COBOL statements following the
DELETE statement in the edit control file up to the next
BASIS-mechanism DELETE or INSERT statement will be included in the
source submitted to your COBOL system. These COBOL source statements are
inserted in place of the last statement omitted by this Basis-mechanism
DELETE statement.
Function
The INSERT statement (under the Basis mechanism) lists lines of COBOL
source to be included in the program submitted to your COBOL system.
General Format
Syntax Rules
- The INSERT reserved word can commence anywhere between columns 1 and
66 of the statement line.
- Subject-sequence must be an unquoted positive numeric integer
(following the rules for integer numeric literals).
General Rules
- Subject-sequence refers to that statement within the COBOL source
file after which the COBOL statement(s) is to be included.
- All those COBOL statements following the INSERT statement in the edit
control file up to the next Basis-mechanism DELETE or INSERT statement
will be included in the source submitted to your COBOL system. At least
one COBOL statement must immediately follow the Basis-mechanism INSERT
statement.
The ++INCLUDE and -INC mechanisms provide another (IBM-mainframe
compatible) means whereby a COBOL program source file or portion of source
code can be included in a file to be compiled.
These special statements are not part of the COBOL language. They must,
in their entirety, be contained on a single line and must be in upper
case.
Function
The -INC statement is used to include all of the data records of one
source file in another source file at compilation time.
General Format
Directives and Run-time Switches
- In addition to Compiler directives which provide flagging and modify
the reserved word list, the following directive may impact either the
syntax or semantics described in this section.
- LIBRARIAN - enables the use of -INC syntax.
Syntax Rules
- -INC must begin in column 1 and be followed by one or more spaces.
- Text-name defines a unique external file-name which conforms to the
rules for user defined words.
- These special statements are not part of the COBOL language. They
must, in their entirety, be contained on a single line and must be in
upper case.
General Rules
- Text-name determines the COBOL source file to be included at this
specific place in the source code.
- Any other text appearing on the line is treated as a comment.
Function
The ++INCLUDE statement is used to include all of the data records of
one source file in another source file at compilation time.
General Format
Directives and Run-time Switches
- In addition to Compiler directives which provide flagging and modify
the reserved word list, the following directive may impact either the
syntax or semantics described in this section.
- PANVALET - enables the use of ++INCLUDE syntax.
Syntax Rules
- ++INCLUDE must begin in column 8, must be in uppercase and must be
followed by one or more spaces.
- Text-name defines a unique external file-name which conforms to the
rules for user defined words.
- These special statements are not part of the COBOL language. They
must, in their entirety, be contained on a single line and must be in
upper case.
General Rules
- Text-name determines the COBOL source file to be included at this
place in the source code.
- Any other text appearing on the line is treated as a comment.
The COBOL system provides a mechanism for selectively compiling part or
all of the COBOL source. To benefit fully from the advantages of
conditional compilation
the use of level
78 (see the chapter Data Division - Data Description) and the
CONSTANT
Compiler directive is recommended. Conditional compilation is
controlled by $IF, $ELSE, $END constructs. It behaves in a similar way to
the COBOL IF construct.
General Notes on all Conditional Compilation Statements
- Conditional compilation statements are indicated by a dollar ($) in
column 7 in fixed format source, or column 1 in free format source of
the COBOL source line followed by one of the key words IF, DISPLAY,
ELSE, END.
- Conditional compilation should not be used to split a COBOL character
string; that is, continuation lines should not be split by conditional
compilation controls.
Function
The $DISPLAY statement displays a message on the standard output device
during compilation or includes a version number in the object file.
General Format
Format 1
Format 2
Syntax Rules
- The whole $DISPLAY statement must appear on a single line.
General Rules
- If a $DISPLAY statement is encountered on a source line that is
ignored by conditional compilation, there is neither a compile-time nor
a runtime effect.
Format 1
- Text-data is displayed on the standard output device during
compilation.
Format 2
- Version-number is the content of the entire source line following the
"=", excluding leading and trailing spaces.
- The character string formed by concatenating "@(#)",
version-number and a null character (binary zero) is included in the
object file, no matter which type of object file is created. If
version-number begins with the characters "@(#)", the system
does not concatenate these characters when forming the character
string..
NoteS:
Function
The most recent $IF condition is reversed. If the now active $IF
condition is true, the source lines following the $ELSE statement are
processed. If the $IF condition is false, COBOL source lines are ignored
until the next conditional compilation line is encountered.
General Format
Syntax Rules
- The whole statement must appear on a single line.
Function
The innermost $IF condition is terminated. The now active $IF condition
is considered. If the active condition is true the source lines following
the $END are processed. If the condition is false, COBOL source lines are
ignored until the next conditional compilation line is encountered.
General Format
Syntax Rules
- The whole statement must appear on a single line.
Function
A $IF statement provides the means whereby selected parts of the source
text are not included in the compilation.
Examples
- An example of using conditional compilation is provided in the Examples
chapter in your Language Reference - Additonal Topics.
General Formats
Format 1
Format 2
Format 3
Syntax Rules
- Constant-name-1 is defined by a level 78 entry or a CONSTANT Compiler
directive.
- If literal-1 is numeric, it must be zero or a positive integer.
- Directive-setting is specified in the same format as it is given in a
$SET statement and may be preceded by NO. However, the following
differences exist from the form used in $SET:
- No spaces are permitted between the NO and directive name
- Hyphens in the directive must be specified exactly
- If the directive has a parameter it may be omitted
- Only directives used in the syntax-check phase and produced in the
directive settings list (see compiler directive SETTINGS) may be
specified for directive-setting
- The whole statement must appear on a single line.
- $IF can be nested within another $IF.
General Rules
- Constant-name-2 is DEFINED if it is the subject of a level 78 entry
or a CONSTANT Compiler directive, otherwise it is NOT DEFINED.
- Directive-setting SET evaluates true if the given setting matches the
actual directive setting. If a parameter is specified then it must also
match.
- The comparison between Directive-setting and the actual directive
setting is not case sensitive.
- If the condition evaluates true the source lines following the $IF
statement are processed. If the condition evaluates false, COBOL source
lines are ignored until the next conditional compilation line is
encountered.
The listing control statements provide a control for producing output
file listings during the compile process.
Three statements are associated with the listing control statements:
- EJECT
- SKIP1, SKIP2 AND SKIP3
-
TITLE.
Function
The EJECT statement tells your COBOL system to print the next line of
source code at the top of the next page.
General Format
Syntax Rules
- EJECT may begin either in area A or in area B, must be the only
statement on the line and may optionally be followed by a period.
General Rules
- The EJECT statement itself is not printed.
Function
The SKIP1, SKIP2 and SKIP3 statements control the vertical spacing of
the so
urce code listing produced by your COBOL system. They specify the
lines to be skipped in the source code listing.
General Format
Syntax Rules
- These statements can begin in area A or in area B, must be the only
statement on the line
and can optionally be followed by a period.
General Rules
- SKIP1 tells your COBOL system to skip one line (double spacing).
SKIP2 tells your COBOL system to skip two lines (triple spacing). SKIP3
tells your COBOL system to skip three lines (quadruple spacing).
- The SKIP statement itself is not printed.
Function
The TITLE statement tells your COBOL system what title to print on the
first line of all subsequent pages of the listing.
General Format
Syntax Rules
- Literal-1 must be nonnumeric and can be followed by a period. It
cannot be a figurative constant.
- The word TITLE can begin either in Area A or Area B and must be the
only statement on the line.
- The TITLE statement can appear anywhere in the compilation group.
General Rules
- Literal-1 will be used as a title on all subsequent pages of the
listing. The default title, which is used until a TITLE directive is
encountered, identifies your COBOL system and its current release level.
- The chosen or default title occupies the left-hand side of the first
line of each page. The remainder of the line gives the date and time the
intermediate code is produced and a page number.
- A second title line is also output containing the name of the main
source file and of the current COPY-file.
- The TITLE statement causes an immediate new page.
- The TITLE statement itself is not printed.
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