# Operators
## Standard operators

Ada allows operator overloading for all standard operators and so the following summaries can only describe the suggested standard operations for each operator. It is quite possible to misuse any standard operator to perform something unusual.
Each operator is either a keyword or a delimiter—hence all operator pages are redirects to the appropriate keyword or delimiter.
Operators have arguments which in the RM are called Left and Right for binary operators, Right for unary operators (indicating the position with respect to the operator symbol).
The list is sorted from lowest precedence to highest precedence.

### Logical operators
#### and

    and $x\land y$, (also keyword and)

#### or

    or $x\lor y$, (also keyword or)

#### xor

    exclusive or $(x\land {\bar {y}})\lor ({\bar {x}}\land y)$, (also keyword xor)

### Relational operators

    Not Equal $x\neq y$, (also special character /=)
    Equal $x=y$, (also special character =)
    Less than $x<y$, (also special character <)
    Less than or equal to ($x\leq y$), (also special character <=)
    Greater than ($x>y$), (also special character >)
    Greater than or equal to ($x\geq y$), (also special character >=)

### Binary adding operators

    Add $x+y$, (also special character +)
    Subtract $x-y$, (also special character -)
    Concatenate , $x$ & $y$, (also special character &)

### Unary adding operators

    Plus sign $+x$, (also special character +)
    Minus sign $-x$, (also special character -)

### Multiplying operator

    Multiply, $x\times y$, (also special character *)
    Divide $x/y$, (also special character /)

#### mod

    modulus (also keyword mod)

#### rem

    remainder (also keyword rem)

### Highest precedence operator

    Power $x^{y}$, (also special character **)

#### not

    logical not $\lnot x$, (also keyword not)

#### abs

    absolute value $|x|$ (also keyword abs)

## Short-circuit control forms

These are not operators and thus cannot be overloaded.

### and then

    e.g. if Y /= 0 and then X/Y > Limit then ...

### or else

    e.g. if Ptr = null or else Ptr.I = 0 then ...

## Membership tests

The Membership Tests also cannot be overloaded because they are not operators.

### in

    element of, $var\in type$, e.g. if I in Positive then, (also keyword in)

### not in

    not element of, $var\notin type$, e.g. if I not in Positive then, (also keywords not in)

### Choice list membership test

This language feature has been introduced in Ada 2012.
Ada 2012 extended the membership tests to include the union (short-circuit or) of several range or value choices.

## See also
### Wikibook

* Ada Programming

### Ada 95 Reference Manual

* 4.5 Operators and Expression Evaluation (Annotated)

### Ada 2005 Reference Manual

* 4.5 Operators and Expression Evaluation (Annotated)

### Ada Quality and Style Guide

* 2.1.3 Alignment of Operators
* 5.7.4 Overloaded Operators
* 5.7.5 Overloading the Equality Operator
Ada Operators :
| and | and then | > | + | abs | & |
| or | or else | >= | - | mod | |
| xor | = | < | * | rem | in |
| not | /= | <= | ** | / | not in |

# Operators: &
## As operator
### Concatenating arrays

Any array type (including fixed Strings) can be concatenated using the & operator. You can also append a single element to an array.

## Common non-standard operations
### Concatenating strings

The & operator is also defined for Bounded_String and Unbounded_String.

## See also
### Wikibook

* Ada Programming/Delimiters
* Ada Programming/Operators

### Ada 95 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.3 Binary Adding Operators (Annotated)
* A.4.4 Bounded-Length String Handling (Annotated)
* A.4.5 Unbounded-Length String Handling (Annotated)

### Ada 2005 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.3 Binary Adding Operators (Annotated)
* A.4.4 Bounded-Length String Handling (Annotated)
* A.4.5 Unbounded-Length String Handling (Annotated)

# Operators: **
## Operator
### Standard Operations
#### Arithmetic Power of

The "**" operator is defined as arithmetic power of for all numeric types.

##### Working Example
## See also
### Wikibook

* Ada Programming
* Ada Programming/Delimiters
* Ada Programming/Operators

### Ada 95 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.6 Highest Precedence Operators (Annotated)

### Ada 2005 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.6 Highest Precedence Operators (Annotated)

# Operators: *
## Operator
### Standard Operations
#### Arithmetic Multiplication

The "*" operator is defined as arithmetic multiplication for all numeric types.

##### Working Example
### Common Non-Standard Operations
#### Character replication

A String is created where a single character is replicated n-times.
In addition to standard Strings this operator is also defined for Bounded_String and Unbounded_String.

##### Working Example

The character replication operator is part of the Ada.Strings.Fixed package. You need to with and use the package to make the operator visible.

#### String replication

A String is created where a source string is replicated n-times.
In addition to standard fixed strings this operator is also defined for Bounded_String and Unbounded_String.

##### Working Example

The string replication operator is part of the Ada.Strings.Fixed package. You need to with and use the package to make the operator visible.

## See also
### Wikibook

* Ada Programming
* Ada Programming/Delimiters
* Ada Programming/Operators

### Ada 95 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.5 Multiplying Operators (Annotated)
* A.4.3 Fixed-Length String Handling (Annotated)
* A.4.4 Bounded-Length String Handling (Annotated)
* A.4.5 Unbounded-Length String Handling (Annotated)

### Ada 2005 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.5 Multiplying Operators (Annotated)
* A.4.3 Fixed-Length String Handling (Annotated)
* A.4.4 Bounded-Length String Handling (Annotated)
* A.4.5 Unbounded-Length String Handling (Annotated)

# Operators: -
## Operator
### Standard Operations
#### Arithmetic Subtraction

The "-" operator is defined as arithmetic subtraction for all numeric types.

##### Usage
#### Minus sign

The "-" unary operator is defined as arithmetic negative sign for all numeric types.

##### Usage
## See also
### Wikibook

* Ada Programming
* Ada Programming/Delimiters
* Ada Programming/Operators
* Ada Programming/Mathematical calculations

### Ada 95 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.3 Binary Adding Operators (Annotated)
* 4.5.4 Unary Adding Operators (Annotated)

### Ada 2005 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.3 Binary Adding Operators (Annotated)
* 4.5.4 Unary Adding Operators (Annotated)

# Operators: /=
## Operator

The operator /= compares two values on inequality. It is predefined for all non limited types. The operator will also be defined if a suitable operator = is available.
Note that in Ada the representation for this operator was chosen for resembling the mathematical symbol $\neq$, in the same way than <= resembles $\leq$, or >= resembles $\geq$.

## See also
### Wikibook

* Ada Programming
* Ada Programming/Delimiters

### Ada 95 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.2 Relational Operators and Membership Tests (Annotated)

### Ada 2005 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.2 Relational Operators and Membership Tests (Annotated)

# Operators: /
## Operator
### Standard operations
#### Arithmetic division

The "/" operator is defined as arithmetic division for all numeric types.

##### Usage
## See also
### Wikibook

* Ada Programming
* Ada Programming/Delimiters
* Ada Programming/Operators
* Ada Programming/Mathematical calculations

### Ada Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.5 Multiplying Operators (Annotated)

# Operators: =
## Operator

The operator = compares two values on equality. It is predefined for all non limited types.

## See also
### Wikibook

* Ada Programming
* Ada Programming/Delimiters

### Ada 95 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.2 Relational Operators and Membership Tests (Annotated)

### Ada 2005 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.2 Relational Operators and Membership Tests (Annotated)

# Operators: abs

This keyword is used for the operator that gets the absolute value of a number.

## See also
### Wikibook

* Ada Programming
* Ada Programming/Keywords

### Ada 95 Reference Manual

* 2.9 Reserved Words (Annotated)
* 4.4 Expressions (Annotated)
* 4.5.6 Highest Precedence Operators (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada 2005 Reference Manual

* 2.9 Reserved Words (Annotated)
* 4.4 Expressions (Annotated)
* 4.5.6 Highest Precedence Operators (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada Quality and Style Guide

* 3.1.3 Capitalization
* 5.5.3 Parenthetical Expressions

# Operators: and
## Logical operator
### Boolean shortcut operator

Shortcut operators are used to make the evaluation of parts of boolean expressions conditional: and then, or else. This should never be done to speed up the evaluation (with modern optimizing compilers, it will possibly not have that effect). The correct use is to prevent the evaluation of expressions known to raise an exception.
In the example above, G (Dog) is only called when the pointer Dog is not null, i.e. it actually points to something.
Actually and then and or else are not operators in the sense of the reference manual, they are called 'Short-circuit Control Forms'. The difference is that (true) operators can be redefined (i.e. overloaded), whereas these cannot. They are however defined for any boolean type.
Since Ada allows parallel evaluation of the arguments for an expression, shortcut operators are not the standard way of evaluating boolean expressions. In any case where the final result of the evaluation is guaranteed to be the same, the compiler is allowed to use a shortcut evaluation.

### Boolean operator on arrays

The and operator is applied to each pair of boolean elements from the left and right arrays. The result has the same bounds as the left operand.

### Bitwise operator

The operator and could be used with modular types to perform bitwise operations.

## Adding interfaces to tagged types

This language feature is only available from Ada 2005 on.

## See also
### Wikibook

* Ada Programming
* Ada Programming/Keywords
* Ada Programming/Operators
* Ada Programming/Keywords/interface

### Ada 95 Reference Manual

* 2.9 Reserved Words (Annotated)
* 4.4 Expressions (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

#### Ada 2005 Reference Manual

* 2.9 Reserved Words (Annotated)
* 3.9.4 Interface Types (Annotated)
* 4.4 Expressions (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada Quality and Style Guide

* 3.1.3 Capitalization

# Operators: >=
## Operator

The operator >= compares two values on greater than or equal to. It is predefined for all discrete types.

## See also
### Wikibook

* Ada Programming
* Ada Programming/Delimiters

### Ada 95 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.2 Relational Operators and Membership Tests (Annotated)

### Ada 2005 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.2 Relational Operators and Membership Tests (Annotated)

# Operators: >
## Operator

The operator > compares two values on being greater. It is predefined for all discrete types.

## See also
### Wikibook

* Ada Programming
* Ada Programming/Delimiters
* Ada Programming/Delimiters/<
* Ada Programming/Delimiters/>>

### Ada 95 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.2 Relational Operators and Membership Tests (Annotated)

### Ada 2005 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.2 Relational Operators and Membership Tests (Annotated)

# Operators: in

This keyword is used in:
* The in and in out mode of subprograms parameters.
* membership tests
* for loops
* quantified expressions

## See also
### Wikibook

* Ada Programming
* Ada Programming/Keywords

### Ada 95 Reference Manual

* 2.9 Reserved Words (Annotated)
* 4.4 Expressions (Annotated)
* 6.1 Subprogram Declarations (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada 2005 Reference Manual

* 2.9 Reserved Words (Annotated)
* 4.4 Expressions (Annotated)
* 6.1 Subprogram Declarations (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada Quality and Style Guide

* 3.1.3 Capitalization

# Operators: <=
## Operator

The operator <= compares two values on less than or equal to. It is predefined for all discrete types.

## See also
### Wikibook

* Ada Programming
* Ada Programming/Delimiters

### Ada 95 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.2 Relational Operators and Membership Tests (Annotated)

### Ada 2005 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.2 Relational Operators and Membership Tests (Annotated)

# Operators: <
## Operator

The operator < compares two values on less than. It is predefined for all discrete types.

## See also
### Wikibook

* Ada Programming
* Ada Programming/Delimiters
* Ada Programming/Delimiters/>
* Ada Programming/Delimiters/<<

### Ada 95 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.2 Relational Operators and Membership Tests (Annotated)

### Ada 2005 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.2 Relational Operators and Membership Tests (Annotated)

# Operators: mod

This keyword is used in the mod operator and in the declaration of modular types.

## See also
### Wikibook

* Ada Programming
* Ada Programming/Keywords

### Ada 95 Reference Manual

* 2.9 Reserved Words (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada 2005 Reference Manual

* 2.9 Reserved Words (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada Quality and Style Guide

* 3.1.3 Capitalization

# Operators: not

This keyword is used in:
* Logical negation operator
* Negative membership test: not in

## See also
### Wikibook

* Ada Programming
* Ada Programming/Keywords

### Ada 95 Reference Manual

* 2.9 Reserved Words (Annotated)
* 4.4 Expressions (Annotated)
* 4.5.6 Highest Precedence Operators (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada 2005 Reference Manual

* 2.9 Reserved Words (Annotated)
* 4.4 Expressions (Annotated)
* 4.5.6 Highest Precedence Operators (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada Quality and Style Guide

* 3.1.3 Capitalization

# Operators: or
## Logical operator
### Boolean shortcut operator

In the below example the function G is only called when F(X) returns the value False.
This shortcut operator is sometimes used to speed up the evaluation of boolean expressions, but the Ada Style Guide recommends to compare the performance of both forms before switching one to the other. In general, it is good idea to use or else in sake of performance only when the second expression involves a function call.
The or else form is also used when the second expression is known to raise an exception unless the first expression is False.
Unlike C/C++, Ada short-cut operators are not the standard way to evaluate boolean expressions. This is because Ada is designed to do by default what is generally safer, but lets the programmer request a different behaviour.

### Boolean operator on arrays

The or operator is applied to each pair of boolean elements from the left and right arrays. The result has the same bounds as the left operand.

### Bitwise operator

The operator or could be used with modular types to perform bitwise operations.

## Select statement
### alternative

See Ada Programming/Tasking#Selective waiting.

### delay

See Ada Programming/Tasking#Timeout.

## See also
### Wikibook

* Ada Programming
* Ada Programming/Keywords
* Ada Programming/Operators

### Ada 95 Reference Manual

* 2.9 Reserved Words (Annotated)
* 4.4 Expressions (Annotated)
* 4.5.1 Logical Operators and Short-circuit Control Forms (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada 2005 Reference Manual

* 2.9 Reserved Words (Annotated)
* 4.4 Expressions (Annotated)
* 4.5.1 Logical Operators and Short-circuit Control Forms (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada Quality and Style Guide

* 3.1.3 Capitalization
* 5.5.5 Short Circuit Forms of the Logical Operators
* 10.5.2 Short-Circuit Operators
* 10.6.3 Bit Operations on Modular Types

# Operators: +
## Operator
### Standard Operations
#### Arithmetic Addition

The "+" operator is defined as arithmetic addition for all numeric types.

#### Plus sign

The "+" operator is defined as arithmetic plus sign for all numeric types.

##### Usage
### Common Non-Standard Operations
#### Type Conversion

The operator plus sign is often used to create a type conversion operator:

## See also
### Wikibook

* Ada Programming
* Ada Programming/Delimiters
* Ada Programming/Operators
* Ada Programming/Mathematical calculations

### Ada 95 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.3 Binary Adding Operators (Annotated)
* 4.5.4 Unary Adding Operators (Annotated)

### Ada 2005 Reference Manual

* 4.4 Expressions (Annotated)
* 4.5.3 Binary Adding Operators (Annotated)
* 4.5.4 Unary Adding Operators (Annotated)

# Operators: rem
## Operator rem

The rem keyword is used as the remainder operator, that is, the remainder of the signed integer division. The following formula applies:

## See also
### Wikibook

* Ada Programming
* Ada Programming/Keywords

### Ada 95 Reference Manual

* 2.9 Reserved Words (Annotated)
* Annex P (informative) Syntax Summary (Annotated)
* 4.5.5 Multiplying Operators (Annotated)

### Ada 2005 Reference Manual

* 2.9 Reserved Words (Annotated)
* Annex P (informative) Syntax Summary (Annotated)
* 4.5.5 Multiplying Operators (Annotated)

### Ada Quality and Style Guide

* 3.1.3 Capitalization

# Operators: xor
## Logical operator
### Boolean operator on arrays

The xor operation is applied to each boolean inside the array.

### Bitwise operator

The operator xor could be used with modular types and also with boolean arrays to perform bitwise operations.

## See also
### Wikibook

* Ada Programming
* Ada Programming/Keywords
* Ada Programming/Operators

### Ada 95 Reference Manual

* 2.9 Reserved Words (Annotated)
* 4.4 Expressions (Annotated)
* 4.5.1 Logical Operators and Short-circuit Control Forms (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada 2005 Reference Manual

* 2.9 Reserved Words (Annotated)
* 4.4 Expressions (Annotated)
* 4.5.1 Logical Operators and Short-circuit Control Forms (Annotated)
* Annex P (informative) Syntax Summary (Annotated)

### Ada Quality and Style Guide

* 3.1.3 Capitalization
* 10.6.3 Bit Operations on Modular Types

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* Do not retitle any existing section to be Entitled "Endorsements" or to conflict in title with any Invariant Section.
* Preserve any Warranty Disclaimers.
If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version's license notice. These titles must be distinct from any other section titles.
You may add a section Entitled "Endorsements", provided it contains nothing but endorsements of your Modified Version by various parties—for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.
You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.
The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.

## 5. COMBINING DOCUMENTS

You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.
The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.
In the combination, you must combine any sections Entitled "History" in the various original documents, forming one section Entitled "History"; likewise combine any sections Entitled "Acknowledgements", and any sections Entitled "Dedications". You must delete all sections Entitled "Endorsements".

## 6. COLLECTIONS OF DOCUMENTS

You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.
You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.

## 7. AGGREGATION WITH INDEPENDENT WORKS

A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an "aggregate" if the copyright resulting from the compilation is not used to limit the legal rights of the compilation's users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.
If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document's Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.

## 8. TRANSLATION

Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.
If a section in the Document is Entitled "Acknowledgements", "Dedications", or "History", the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.

## 9. TERMINATION

You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.
However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.
Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.

## 10. FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See http://www.gnu.org/copyleft/.
Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy's public statement of acceptance of a version permanently authorizes you to choose that version for the Document.

## 11. RELICENSING

"Massive Multiauthor Collaboration Site" (or "MMC Site") means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A "Massive Multiauthor Collaboration" (or "MMC") contained in the site means any set of copyrightable works thus published on the MMC site.
"CC-BY-SA" means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.
"Incorporate" means to publish or republish a Document, in whole or in part, as part of another Document.
An MMC is "eligible for relicensing" if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.
The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.

# How to use this License for your documents

To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:
    Copyright (c) YEAR YOUR NAME.
    Permission is granted to copy, distribute and/or modify this document
    under the terms of the GNU Free Documentation License, Version 1.3
    or any later version published by the Free Software Foundation;
    with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
    A copy of the license is included in the section entitled "GNU
    Free Documentation License".
If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the "with...Texts." line with this:
    with the Invariant Sections being LIST THEIR TITLES, with the
    Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.
If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.