Reference:Declare and Local Directives - Revision history

Maurice: Precision about 40 char limited version number

2021-07-02T20:47:30Z

Precision about 40 char limited version number

Clipka: /* Declaring identifiers */ canonicalized version numbers

2021-06-09T13:19:04Z

Declaring identifiers: canonicalized version numbers

Jholsenback: version changes

2017-06-26T10:09:20Z

version changes

Jholsenback: adding tuple

2016-12-31T12:57:15Z

adding tuple

Clipka: Indexentries fix

2016-12-16T15:17:57Z

Indexentries fix

Jholsenback: added note

2016-12-14T11:57:21Z

added note

Jholsenback: removing superseded passage

2016-12-13T17:58:57Z

removing superseded passage

Jholsenback: identifier length update

2016-12-01T15:09:15Z

identifier length update

Jholsenback: tag changed

2016-07-17T13:33:54Z

tag changed

Clipka: /* Identifier Name Collisions */

2016-05-05T17:06:28Z

Identifier Name Collisions

@@ Line 29: / Line 29: @@
 <p>Where <em>IDENTIFIER</em> is the name of the identifier that is at least one character long and <em>RVALUE</em> is any of the listed items.</p>
 <p>The syntax for each is in the corresponding section of this language reference.</p>
-<p class="Note"><strong>Note:</strong> In previous versions identifier names <em>were</em> limited to 40 characters. There has been a {{Change}} removing that restriction.</p>
+<p class="Note"><strong>Note:</strong> In versions prior to 3.6.2, identifier names <em>were</em> limited to 40 characters. There has been a {{Change}} removing that restriction.</p>
 <p>Here are some examples.</p>
 <pre>

@@ Line 50: / Line 50: @@
 </pre>
-<p class="Note"><strong>Note:</strong> There should be a semi-colon after the expression in all float,vector and color identifier declarations. This semi-colon is introduced in POV-Ray version 3.1. If omitted, it generates a warning and some macros may not work properly. Semicolons after other declarations are optional.</p>
+<p class="Note"><strong>Note:</strong> There should be a semi-colon after the expression in all float,vector and color identifier declarations. This semi-colon is introduced in POV-Ray v3.1. If omitted, it generates a warning and some macros may not work properly. Semicolons after other declarations are optional.</p>
 <p>Declarations, like most language directives, can appear almost anywhere in the file, even within other statements. For example:</p>
 <pre>
@@ Line 67: / Line 67: @@
 <p class="Note"><strong>Note:</strong> Object identifiers use the generic wrapper statement <code>object{</code> ... <code>}</code>. You do not need to know what kind of object it is.</p>
 <p>Declarations may be nested inside each other within limits. In the example in the previous section you could declare the entire union as a object. However for technical reasons there are instances where you may not use any language directive inside the declaration of floats, vectors or color expressions. Although these limits have been loosened somewhat since POV-Ray
-.1, they still exist.</p>
+v3.1, they still exist.</p>
 <p>Identifiers declared within <code>[[Reference:User Defined Macros#The macro Directive|:#macro|#macro]]</code> ...
 <code>[[Reference:Conditional Directives#The if...else...end Directives|:#end|#end]]</code> blocks are not created at the time the macro is defined. They are only created at the time the macro is actually invoked. Like all other items inside such a <code>#macro</code> definition, they are ignored when the macro is defined.</p>

@@ Line 272: / Line 272: @@
 identifiers and &quot;most recent&quot; for existing identifiers.</p>
-<p>{{New}} in version 3.7.1: To circumvent the pitfalls of identifier name collisions, two <em>pseudo-dictionaries</em> are provided to specifically refer to identifiers at either the global or the most local scope. See also the [[Reference:Array|Array]] section for more information.</p>
+<p>{{New}} in version 3.8: To circumvent the pitfalls of identifier name collisions, two <em>pseudo-dictionaries</em> are provided to specifically refer to identifiers at either the global or the most local scope. See also the [[Reference:Array|Array]] section for more information.</p>
 ==Destroying Identifiers with undef==

@@ Line 70: / Line 70: @@
 <p>Identifiers declared within <code>[[Reference:User Defined Macros#The macro Directive|:#macro|#macro]]</code> ...
 <code>[[Reference:Conditional Directives#The if...else...end Directives|:#end|#end]]</code> blocks are not created at the time the macro is defined. They are only created at the time the macro is actually invoked. Like all other items inside such a <code>#macro</code> definition, they are ignored when the macro is defined.</p>
 ==declare vs. local==

@@ Line 8: / Line 8: @@
 changes many values. There are several built-in identifiers which POV-Ray
 declares for you. See the sections: [[Reference:Numeric Expressions#Built-in Variables|:Float, built-in variables|Built-in Variables]] and [[Reference:Numeric Expressions#Built-in Constants|:Vector, built-in identifiers|Built-in Vector Identifiers]] for details.</p>
 {{#indexentry:Identifiers, declaring}}
 {{#indexentry:Directives, language, identifiers}}
 {{#indexentry:#declare}}
 {{#indexentry:declare}}
 <p>An identifier is declared as follows.</p>
 <pre>
@@ Line 70: / Line 71: @@
 <code>[[Reference:Conditional Directives#The if...else...end Directives|:#end|#end]]</code> blocks are not created at the time the macro is defined. They are only created at the time the macro is actually invoked. Like all other items inside such a <code>#macro</code> definition, they are ignored when the macro is defined.</p>
 {{#indexentry:Directives, language, #declare vs. #local}}
 <p>Identifiers may be declared either global using <code>[[Reference:Declare and Local Directives#Declaring identifiers|:#declare|#declare]]</code> or local using the <code>[[Reference:Declare and Local Directives#Declaring identifiers|:#local|#local]]</code> directive.</p>
 <p>
@@ Line 107: / Line 107: @@
 Local identifiers may be specifically released early using <code>[[Reference:Declare and Local Directives#Destroying Identifiers with undef|:#undef|#undef]]</code> but in general there is no need to do so. See [[Reference:Declare and Local Directives#Destroying Identifiers with undef|:#undef|Destroying Identifiers]].</p>
 {{#indexentry:Directives, name collisions}}
 <p>Local identifiers may have the same names as previously declared
 identifiers. In this instance, the most recent, most local identifier takes
@@ Line 221: / Line 220: @@
 <p>{{New}} in version 3.7.1: To circumvent the pitfalls of identifier name collisions, two <em>pseudo-dictionaries</em> are provided to specifically refer to identifiers at either the global or the most local scope. See also the [[Reference:Array|Array]] section for more information.</p>
 {{#indexentry:Identifiers, destroying}}
 {{#indexentry:Directives, language, identifiers, destroying}}
@@ Line 226: / Line 226: @@
 {{#indexentry:#undef}}
 {{#indexentry:undef}}
 <p>Identifiers created with <code>#declare</code> will generally persist until parsing is complete. Identifiers created with <code>#local</code> will persist until the end of the macro or include file in which they were created. You may however un-define an identifier using the <code>#undef</code> directive. For example:</p>
 <pre>
@@ Line 235: / Line 233: @@
 <p>See also [[Reference:Conditional Directives#The ifdef and ifndef Directives|:#ifdef|The #ifdef and #ifndef Directives]].</p>
 {{#indexentry:deprecated}}
 <p>The ability to add a <code>deprecated</code> flag to a <code>#declare</code> has been added. This is to aid in migrating scenes away from old constructs (e.g. old textures). The usage is illustrated below:</p>
 <pre>

@@ Line 239: / Line 239: @@
 {{#indexentry:global, function}}
 {{#indexentry:local, function}}
-<p>{{New.3.7.1}} To circumvent the pitfalls of identifier name collisions,
+<p>{{New}} in version 3.7.1: To circumvent the pitfalls of identifier name collisions,
 two pseudo-functions are provided to specifically refer to identifiers
 at either the global or the most local scope:</p>

@@ Line 166: / Line 166: @@
 <p>The main version of <code>A</code> is hidden and a new <code>A</code> is
 created. This new <code>A</code> is also available inside <code>
-MyMacro</code> because <code>MyMacro</code> is nested inside <code>
+MyMacro</code> because <code>MyMacro</code> is called from inside <code>
 myinc.inc</code>. Once you exit <code>myinc.inc</code>, the local <code>
 A</code> is destroyed and the original <code>A</code> with its value of