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**OMIT(**//terminator// [,//expression//]**)**

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| **OMIT** | Specifies a block of source code lines to be omitted from the compilation. |
| //terminator// | A string constant that marks the last line of a block of source code. |
| //expression// | An expression allowing conditional execution of the OMIT. The expression is either an EQUATE whose value is zero or one, EQUATE = integer, or one of the other conditional operators described below.. |

The **OMIT** directive specifies a block of source code lines to be omitted from the compilation. These lines may contain source code comments or a section of code that is to be conditionally compiled. The omitted block begins with the OMIT directive and ends with the line that contains the same string constant as the //terminator//. The entire terminating line is included in the OMIT block.

The optional //expression// parameter permits conditional OMIT. The form of the //expression// is fixed. It is the label of an EQUATE statement, or a Conditional Switch set in the Project System, and may be followed by a valid operator and an integer constant.

The following conditional operators are supported:

//Expressions// may be one of the following forms:

| <;equate> |  |  |
| <;equate> | = | <;integer constant> |
| <;equate> | <;> | <;integer constant> |
| <;equate> | > | <;integer constant> |
| <;equate> | <; | <;integer constant> |
| <;equate> | >= | <;integer constant> |
| <;equate> | <;= | <;integer constant> |

The OMIT directive executes only if the //expression// is true. Therefore, the code between OMIT and the //terminator// is compiled only if the //expression// is not true. If the //expression// contains an EQUATE that has not yet been defined, then the referenced EQUATE is assumed to be zero (0). COMPILE and OMIT are opposites.

Every source/include file can have nested OMIT/COMPILE blocks with a maximum nesting equal to 8 with a condition that when evaluated does not omit source, plus one additional

OMIT/COMPILE with a condition evaluated to omit source code.

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The OMIT compiler directive is not used by the ABC Application Class Parser.

**Example:**

** ****OMIT('**END**')****             !Unconditional OMIT**

** !Main Program Loop**

****END****

** OMIT('***',_WIDTH32_)****       !OMIT only if application is 32-bit**

**SIGNED   EQUATE(SHORT)**

** *****

** COMPILE('***',_WIDTH32_)    !COMPILE only if application is 32-bit**

**SIGNED   EQUATE(LONG)**

** *****

**OMIT('EndOfFile',OnceOnly)****   !Compile only the first time encountered because the **

**OnceOnly EQUATE(1)           ! OnceOnly EQUATE is defined after the COMPILE that **

**                             ! references it, so a second pass during the same **

**                             ! compilation will not re-compile the code**

**Demo EQUATE(0)               !Specify the Demo EQUATE value**

** CODE**

** ****OMIT('EndDemoChk',Demo = 0)**** !OMIT only if Demo is turned off**

**  DO DemoCheck               !Check for demo limits passed**

** !EndDemoChk                 !End of omitted code**

**! EndOfFile**

**!The following example below shows how OMIT and COMPILE can be nested**

**COMPILE**** ('**32bit**',_width32_) !outer COMPILE**

** COMPILE**** ('*debug*',_debug_)**

** DEBUGGER::BUTTONLIST Equate('&amp;Continue|&amp;Halt|&amp;Debug')**

** !end-**** COMPILE**** ('*debug*',_debug_)**

** OMIT**** ('*debug*',_debug_)**

** DEBUGGER::BUTTONLIST Equate('&amp;Continue|&amp;Halt')**

** !end-**** OMIT**** ('*debug*',_debug_)**

**!end-**** COMPILE**** ('**32bit**',_width32_) !end outer COMPILE**

**OMIT ****('**32bit**',_width32_)**

** DEBUGGER::BUTTONLIST Equate('&amp;Continue|&amp;Halt')**

**!end-**** OMIT**** ('**32bit**',_width32_)**

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The compiler reads and parses source/include files by blocks. If the end of an OMIT/COMPILE block (terminator string) is found in the current block, the compiler either with skip the text up to terminator or will continue to parse the file - depending on whether you are using OMIT or COMPILE and what condition. If the terminator string is found within the current block and parsing is continuing, nested OMIT/COMPILE statements are allowed. If the terminator string is not found, nested OMIT/COMPILE statement in this block is not allowed.

In summary, nesting of OMIT/COMPILE statements is dependent on the current compiler block. Use of conditions in OMIT/COMPILE statements and possibility to define complex conditions as EQUATEs are allowed to avoid excessive nesting of OMIT/COMPILE statements.

**See Also:**

[[predefined compiler flags.htm|Predefined Compiler Flags]]

[[compile  specify source to compile .htm|COMPILE]]

[[equate  assign label .htm|EQUATE]]