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= Text production rules =
 
= Text production rules =
  
h3. Text Production Rules
+
== Text Production Rules ==
  
+
=== Overview ===
h4. Overview
+
  
This is still a draft and is only provided as information. Though this document is still missing some formatting and examples, it can be used to get a precise idea as to how indentation and carriage returns are handled in Acceleo.
+
This is still a draft and is only provided as information. Though this document is still missing some formatting and examples, it can be used to get a precise idea as to how indentation and carriage returns are handled in Acceleo.  
  
h4. Definitions
+
=== Definitions ===
  
Text production rules will apply to all body elements.
+
Text production rules will apply to all body elements. Each body element can be either stand alone or embedded within other body elements. It will be easier to understand text production rules by splitting these body elements in five main categories : expressions, static text, comments, template invocation and blocks.  
Each body element can be either stand alone or embedded within other body elements.
+
It will be easier to understand text production rules by splitting these body elements in five main categories : expressions, static text, comments, template invocation and blocks.
+
  
"Blocks" include template, for, if, let, protected area, file, trace and macro blocks.
+
"Blocks" include template, for, if, let, protected area, file, trace and macro blocks. A block will be considered ��stand-alone�� if it is either one of:  
A block will be considered ��stand-alone�� if it is either one of:
+
  
- A single line block that is not surrounded with any other body element, except
+
- A single line block that is not surrounded with any other body element, except for white spaces, block tails and comments;
  for white spaces, block tails and comments;
+
- A multi-line block that is not surrounded with any other body element, except
+
  for white spaces, block tails and comments, on the lines where the block head
+
  and tail occur.
+
  
Any block that does not fall into these categories will be considered an
+
- A multi-line block that is not surrounded with any other body element, except for white spaces, block tails and comments, on the lines where the block head and tail occur.
"embedded" block.
+
  
h5. Examples
+
Any block that does not fall into these categories will be considered an "embedded" block.  
  
 +
==== Examples ====
  
h6. Stand-alone single-line blocks
+
===== Stand-alone single-line blocks =====
  
 +
Nothing relevant for generation between the line start and the block head, nothing relevant between the block tail and the line end; both head and tail on the same line. All of the following are in this category.
  
Nothing relevant for generation between the line start and the block head, nothing relevant between the block tail and the line end; both head and tail on the same line.
+
[for (Sequence{false, false, false})][self/][/for]
All of the following are in this category.
+
[if (true)]output[/if]
 +
[for (Sequence{false, false, false})][self/][/for]
 +
[/if][if (true)]output [/if]
 +
[/if][comment .../] [if (true)]output[/if]
  
::
+
===== Embedded single-line blocks =====
  
  [for (Sequence{false, false, false})][self/][/for]
+
Head and tail of the block are on the same line, but there is something relevant to the generation other than the block on that same line.
  
----
+
Some text[for (Sequence{false, false, false})]output[/for]
 +
[if (true)]output[/if] and some text
 +
[for (Sequence{false, false, false})] [self/][/for] and some text.
  
::
+
===== Stand-alone multi-line blocks =====
  
  [if (true)]output[/if]
+
Nothing relevant for generation between the line start and the block head, nothing relevant between the block tail and the line end; head and tail on different lines.  
 
+
----
+
 
+
::
+
 
+
      [for (Sequence{false, false, false})][self/][/for]
+
 
+
----
+
 
+
::
+
 
+
  [/if] [if (true)]output[/if]
+
 
+
----
+
 
+
::
+
 
+
  [/if] [comment .../] [if (true)]output[/if]
+
 
+
h6. Embedded single-line blocks
+
 
+
 
+
Head and tail of the block are on the same line, but there is something relevant to the generation other than the block on that same line.
+
 
+
::
+
 
+
  Some text[for (Sequence{false, false, false})]output[/for]
+
 
+
----
+
 
+
::
+
 
+
  [if (true)]output[/if] and some text
+
 
+
----
+
 
+
::
+
 
+
  [for (Sequence{false, false, false})] [self/][/for] and some text.
+
 
+
h6. Stand-alone multi-line blocks
+
 
+
 
+
Nothing relevant for generation between the line start and the block head, nothing relevant between the block tail and the line end; head and tail on different lines.
+
 
+
::
+
  
 
   [for (Sequence{false, false, false})]
 
   [for (Sequence{false, false, false})]
 
       [self/]
 
       [self/]
 
   [/for]
 
   [/for]
 
----
 
 
::
 
  
 
   [if (true)]output
 
   [if (true)]output
 
   [/if]
 
   [/if]
 
----
 
 
::
 
  
 
   [if (true)]
 
   [if (true)]
 
       output[/if]
 
       output[/if]
 
----
 
 
::
 
  
 
   [comment]Generate booleans [/comment][for (Sequence{false, false, false})]
 
   [comment]Generate booleans [/comment][for (Sequence{false, false, false})]
 
       [self/][/for]
 
       [self/][/for]
  
----
+
  [for (Sequence{false, false, false})]
 +
  [self/]
 +
  [/for]
  
::
+
===== Embedded multi-line blocks =====
  
      [for (Sequence{false, false, false})]
+
Head and tail of the block are on different lines, but there is something relevant to the generation other than the block on that same line.
      [self/]
+
      [/for]
+
  
h6. Embedded multi-line blocks
+
text[for (Sequence{false, false, false})]
 
+
 
+
Head and tail of the block are on different lines, but there is something relevant to the generation other than the block on that same line.
+
 
+
::
+
 
+
  text[for (Sequence{false, false, false})]
+
 
       [self/]
 
       [self/]
  [/for]
+
[/for]
  
----
+
if (true)]
 
+
::
+
 
+
  [if (true)]
+
 
       output[/if] text
 
       output[/if] text
  
 +
=== Identifying Body Element Boundaries ===
  
h4. Identifying Body Element Boundaries
+
==== Block Body ====
  
 
+
===== Single-line block =====
h5. Block Body
+
Body starts after the closing bracket of the block head and ends before the starting bracket of the block tail.
 
+
**Single-line block**
+
  Body starts after the closing bracket of the block head and ends before the
+
  starting bracket of the block tail.
+
 
    
 
    
**Multi-line block**
+
===== Multi-line block =====
  If the closing bracket of the block head is directly followed by a new line,
+
If the closing bracket of the block head is directly followed by a new line, the block's body starts at the beginning of the next line after the block head. Otherwise the block's body starts after the closing bracket of its head. The body ends before the starting bracket of the block tail, be it directly preceded by a new line or not.
  the block's body starts at the beginning of the next line after the block head.
+
  Otherwise the block's body starts after the closing bracket of its head.
+
  The body ends before the starting bracket of the block tail, be it directly
+
  preceded by a new line or not.
+
 
    
 
    
**Special handling of "Template" blocks**
+
===== Special handling of "Template" blocks =====
  If the last characters preceding the starting bracket of the block tail is a
+
If the last characters preceding the starting bracket of the block tail is a new line followed by optional white spaces, the template body ends before the last new line character preceding its tail.
  new line followed by optional white spaces, the template body ends before the
+
  last new line character preceding its tail.
+
  
 +
==== Static Text ====
  
Static Text
+
We need to define the concept of line relevance to properly identify these boundaries. For this purpose, we will describe as "white spaces" the white space characters contained in a static text, whatever their position in the text.  
-----------------
+
We need to define the concept of line relevance to properly identify these boundaries. For this purpose, we will describe as "white spaces" the white space characters contained in a static text, whatever their position in the text.
+
  
A line is considered "relevant" if it contains anything else than white spaces, block head, block tail and comment.
+
A line is considered "relevant" if it contains anything else than white spaces, block head, block tail and comment. Note, however, that lines consisting of white spaces *only* are also considered relevant.  
Note, however, that lines consisting of white spaces *only* are also considered relevant.
+
  
- If a static text is entirely located on a non relevant line, it does not
+
- If a static text is entirely located on a non relevant line, it does not produce any text.
  produce any text.
+
- If a static text starts on a non relevant line, all characters located on this
+
  line are ignored and the static text is considered to start with the character
+
  after its very first new line character.
+
- If a static text ends on a non relevant line, all characters located on this
+
  line are ignored and the static text is considered to end with the character
+
  before its very last new line character.
+
- *Special handling of static text following a ��protected area�� block:*
+
  all white spaces following a protected area tail are retained, including the
+
  new line character.
+
  The static text then starts right after the closing bracket of the protected
+
  area tail.
+
  
Rules
+
- If a static text starts on a non relevant line, all characters located on this  line are ignored and the static text is considered to start with the character after its very first new line character.
===========================================
+
Considering the boundaries outlined in section
+
`Identifying Body Element Boundaries`_ above, the text production rules stand as follows:
+
  
- The text produced by the execution of expressions is output as is;
+
- If a static text ends on a non relevant line, all characters located on this line are ignored and the static text is considered to end with the character before its very last new line character.
- The text produced by the execution of static text is output as is;
+
- Comments do not produce any text;
+
- Each line of the text produced by a template invocation will be indented to
+
  match the indentation of the line sporting the invocation;
+
- The text produced by the execution of embedded blocks, be they multi-line
+
  blocks or single line blocks, is output as is along with all text produced by
+
  the surrounding body elements.
+
- The text produced by the execution of stand-alone, single line blocks is
+
  output as is. White spaces located before and after the block are retained;
+
- The text produced by the execution of stand-alone, multi-line blocks will be
+
  output as is considering the aforementioned boundaries: if the very first
+
  character of the block body is a new line, it is ignored.
+
  Please note that if a stand-alone, multi-line block doesn't produce any text,
+
  not even a new line character will be present in the resulting text.
+
  
Examples
+
- Special handling of static text following a '''''protected area''''' block: all white spaces following a protected area tail are retained, including the new line character. The static text then starts right after the closing bracket of the protected area tail.
===========================================
+
  
In the following examples, invisible characters have been materialized:
+
===== Rules =====
 +
Considering the boundaries outlined in section `Identifying Body Element Boundaries`_ above, the text production rules stand as follows:  
  
 +
- The text produced by the execution of expressions is output as is; - The text produced by the execution of static text is output as is;
  
| |inter|    | indicates a space character          |
+
-Comments do not produce any text; - Each line of the text produced by a template invocation will be indented to match the indentation of the line sporting the invocation;
  
| |tab|      | indicates a horizontal tab character |
+
-The text produced by the execution of embedded blocks, be they multi-line  blocks or single line blocks, is output as is along with all text produced by the surrounding body elements.
  
| |return|  | indicates a carriage return          |
+
- The text produced by the execution of stand-alone, single line blocks is  output as is. White spaces located before and after the block are retained;
  
 +
- The text produced by the execution of stand-alone, multi-line blocks will be  output as is considering the aforementioned boundaries: if the very first character of the block body is a new line, it is ignored. Please note that if a stand-alone, multi-line block doesn't produce any text, not even a new line character will be present in the resulting text.
  
Blocks
+
===== Examples =====
-----------------
+
In the following examples, invisible characters have been materialized:
 +
* |inter| indicates a space character
 +
* |tab| indicates a horizontal tab character
 +
* |return| indicates a carriage return
  
Embedded Blocks ______________________________________
+
===Blocks===
  
Example 1
+
==== Embedded Blocks ====
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
 
The Acceleo code:
 
The Acceleo code:
  
Line 233: Line 126:
 
   ``-`` |inter| @')]output[/for]@
 
   ``-`` |inter| @')]output[/for]@
  
produces the following result:
+
produces the following result:  
  
 
   @Some@ |inter| @text@ |inter| @output@ |inter| @-@ |inter| @output@
 
   @Some@ |inter| @text@ |inter| @output@ |inter| @-@ |inter| @output@
 
   |inter| @-@ |inter| @output@
 
   |inter| @-@ |inter| @output@
 
    
 
    
----
 
 
Example 2
 
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
 
 
The Acceleo code:
 
The Acceleo code:
  
Line 247: Line 136:
 
   |inter| @text@
 
   |inter| @text@
  
produces:
+
produces:  
  
 
   @output@ |inter| @and@ |inter| @some@ |inter| @text@
 
   @output@ |inter| @and@ |inter| @some@ |inter| @text@
  
----
 
 
Example 3
 
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
 
 
The Acceleo code:
 
The Acceleo code:
  
Line 260: Line 145:
 
   @[self/][/for]@ |inter| @and@ |inter| @some@ |inter| @text@
 
   @[self/][/for]@ |inter| @and@ |inter| @some@ |inter| @text@
  
produces:
+
produces:  
  
 
   |tab| |inter| @false@ |inter| @false@ |inter| @and@ |inter| @some@
 
   |tab| |inter| @false@ |inter| @false@ |inter| @and@ |inter| @some@
 
   |inter| @text@
 
   |inter| @text@
  
----
+
The Acceleo code:  
 
+
Example 4
+
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
The Acceleo code:
+
  
 
   ``text[for`` |inter| ``(Sequence{false,`` |inter| @false})]@ |return|
 
   ``text[for`` |inter| ``(Sequence{false,`` |inter| @false})]@ |return|
Line 277: Line 158:
 
   @[/for]text@
 
   @[/for]text@
  
produces:
+
produces:  
  
 
   @text@ |tab| @false@ |return|
 
   @text@ |tab| @false@ |return|
Line 285: Line 166:
 
   @text@
 
   @text@
  
----
+
The Acceleo code:  
 
+
Example 5
+
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
The Acceleo code:
+
  
 
   ``text[for`` |inter| ``(Sequence{false,`` |inter| @false})]@ |return|
 
   ``text[for`` |inter| ``(Sequence{false,`` |inter| @false})]@ |return|
Line 295: Line 172:
 
   |tab| @output[/for]text@
 
   |tab| @output[/for]text@
  
produces:
+
produces:  
  
 
   @text@ |tab| @output@ |tab| @outputtext@ |return|
 
   @text@ |tab| @output@ |tab| @outputtext@ |return|
  
 
+
==== Stand-alone single-line blocks ====
Stand-alone single-line blocks ___________________________________________
+
The Acceleo code:  
 
+
Example 1
+
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
The Acceleo code:
+
  
 
   ``[for`` |inter| ``(Sequence{false,`` |inter| @false,@ |inter|
 
   ``[for`` |inter| ``(Sequence{false,`` |inter| @false,@ |inter|
 
   @false})][self/][/for]@
 
   @false})][self/][/for]@
  
produces:
+
produces:  
  
 
   @falsefalsefalse@
 
   @falsefalsefalse@
  
----
+
The Acceleo code:  
 
+
Example 2
+
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
The Acceleo code:
+
  
 
   ``[if`` |inter| @(true)]output[/if]@
 
   ``[if`` |inter| @(true)]output[/if]@
  
produces:
+
produces:  
  
 
   @output@
 
   @output@
  
----
+
The Acceleo code:  
 
+
Example 3
+
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
The Acceleo code:
+
  
 
   |tab| ``[for`` |inter| ``(Sequence{false,`` |inter| @false,@ |inter|
 
   |tab| ``[for`` |inter| ``(Sequence{false,`` |inter| @false,@ |inter|
 
   @false})][self/][/for]@
 
   @false})][self/][/for]@
  
produces:
+
produces:  
  
 
   |tab| @falsefalsefalse@
 
   |tab| @falsefalsefalse@
  
----
+
The Acceleo code:  
 
+
Example 4
+
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
The Acceleo code:
+
  
 
   ``[/if]`` |tab| |tab| ``[if`` |inter| @(true)]output[/if]@
 
   ``[/if]`` |tab| |tab| ``[if`` |inter| @(true)]output[/if]@
  
produces:
+
produces:  
  
 
   |tab| |tab| @output@
 
   |tab| |tab| @output@
  
----
+
The Acceleo code:  
 
+
Example 5
+
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
The Acceleo code:
+
  
 
   ``[/if]`` |inter| ``[comment .../]`` |tab| ``[if`` |inter| @(true)]output[/if]@
 
   ``[/if]`` |inter| ``[comment .../]`` |tab| ``[if`` |inter| @(true)]output[/if]@
  
produces:
+
produces:  
  
 
   |inter| |tab| @output@
 
   |inter| |tab| @output@
  
Stand-alone multi-line blocks ___________________________________________
+
==== Stand-alone multi-line blocks ====
 
+
The Acceleo code:  
Example 1
+
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
The Acceleo code:
+
  
 
   ``[for`` |inter| ``(Sequence{false,`` |inter| ``false,`` |inter| @false})]@ |return|
 
   ``[for`` |inter| ``(Sequence{false,`` |inter| ``false,`` |inter| @false})]@ |return|
  
 
   |tab| @[self/]@ |return|
 
   |tab| @[self/]@ |return|
+
 
 
   @[/for]@
 
   @[/for]@
  
produces:
+
produces:  
  
 
   |tab| @false@ |return|
 
   |tab| @false@ |return|
Line 382: Line 236:
 
   |tab| @false@ |return|
 
   |tab| @false@ |return|
  
 
+
The Acceleo code:  
----
+
 
+
Example 2
+
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
The Acceleo code:
+
  
 
   ``[if`` |inter| @(false)]output@ |return|
 
   ``[if`` |inter| @(false)]output@ |return|
Line 393: Line 242:
 
   @[/if]@
 
   @[/if]@
  
produces nothing, neither whitespace nor empty line.
+
produces nothing, neither whitespace nor empty line.  
  
----
+
The Acceleo code:  
 
+
Example 3
+
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
The Acceleo code:
+
  
 
   ``[if`` |inter| @(true)]@ |return|
 
   ``[if`` |inter| @(true)]@ |return|
Line 405: Line 250:
 
   |tab| @output[/if]@
 
   |tab| @output[/if]@
  
produces:
+
produces:  
  
 
   |tab| @output@
 
   |tab| @output@
  
----
+
The Acceleo code:  
 
+
Example 4
+
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
The Acceleo code:
+
  
 
   ``[comment]for`` |inter| @loop[/comment][for@ |inter|
 
   ``[comment]for`` |inter| @loop[/comment][for@ |inter|
Line 419: Line 260:
  
 
   |tab| ``[if`` |inter| @(self)]@ |return|
 
   |tab| ``[if`` |inter| @(self)]@ |return|
+
 
 
   |tab| |tab| @[self/]@ |return|
 
   |tab| |tab| @[self/]@ |return|
+
 
 
   |tab| @[/if]@ |return|
 
   |tab| @[/if]@ |return|
+
 
 
   @[/for]@
 
   @[/for]@
  
produces nothing, neither whitespace nor empty line.
+
produces nothing, neither whitespace nor empty line.  
  
----
+
The Acceleo code:  
 
+
Example 5
+
08:07, 11 January 2011 (UTC)08:07, 11 January 2011 (UTC)~~
+
The Acceleo code:
+
  
 
   |tab| ``[for`` |inter| ``(Sequence{false,`` |inter| @false,@ |inter|
 
   |tab| ``[for`` |inter| ``(Sequence{false,`` |inter| @false,@ |inter|
Line 438: Line 275:
  
 
   @[self/]@ |return|
 
   @[self/]@ |return|
+
 
 
   |tab| @[/for]@ |return|
 
   |tab| @[/for]@ |return|
  
 
+
<br> produces:  
produces:
+
  
 
   @false@ |return|
 
   @false@ |return|
Line 449: Line 285:
  
 
   @false@ |return|
 
   @false@ |return|
 +
 +
<br> {{Acceleo-index}}
 +
 +
[[Category:Modeling]] [[Category:M2T]] [[Category:Acceleo]]

Revision as of 03:13, 17 August 2012

Text production rules

Text Production Rules

Overview

This is still a draft and is only provided as information. Though this document is still missing some formatting and examples, it can be used to get a precise idea as to how indentation and carriage returns are handled in Acceleo.

Definitions

Text production rules will apply to all body elements. Each body element can be either stand alone or embedded within other body elements. It will be easier to understand text production rules by splitting these body elements in five main categories : expressions, static text, comments, template invocation and blocks.

"Blocks" include template, for, if, let, protected area, file, trace and macro blocks. A block will be considered ��stand-alone�� if it is either one of:

- A single line block that is not surrounded with any other body element, except for white spaces, block tails and comments;

- A multi-line block that is not surrounded with any other body element, except for white spaces, block tails and comments, on the lines where the block head and tail occur.

Any block that does not fall into these categories will be considered an "embedded" block.

Examples

Stand-alone single-line blocks

Nothing relevant for generation between the line start and the block head, nothing relevant between the block tail and the line end; both head and tail on the same line. All of the following are in this category.

[for (Sequence{false, false, false})][self/][/for]
[if (true)]output[/if]
[for (Sequence{false, false, false})][self/][/for]
[/if][if (true)]output [/if]
[/if][comment .../] [if (true)]output[/if]
Embedded single-line blocks
Head and tail of the block are on the same line, but there is something relevant to the generation other than the block on that same line. 
Some text[for (Sequence{false, false, false})]output[/for]
[if (true)]output[/if] and some text
[for (Sequence{false, false, false})]	[self/][/for] and some text.
Stand-alone multi-line blocks

Nothing relevant for generation between the line start and the block head, nothing relevant between the block tail and the line end; head and tail on different lines.

 [for (Sequence{false, false, false})]
     [self/]
 [/for]
 [if (true)]output
 [/if]
 [if (true)]
     output[/if]
 [comment]Generate booleans [/comment][for (Sequence{false, false, false})]
     [self/][/for]
 [for (Sequence{false, false, false})]
 [self/]
 [/for]
Embedded multi-line blocks

Head and tail of the block are on different lines, but there is something relevant to the generation other than the block on that same line.

text[for (Sequence{false, false, false})]
     [self/]
[/for]
if (true)]
     output[/if] text

Identifying Body Element Boundaries

Block Body

Single-line block

Body starts after the closing bracket of the block head and ends before the starting bracket of the block tail.

Multi-line block

If the closing bracket of the block head is directly followed by a new line, the block's body starts at the beginning of the next line after the block head. Otherwise the block's body starts after the closing bracket of its head. The body ends before the starting bracket of the block tail, be it directly preceded by a new line or not.

Special handling of "Template" blocks

If the last characters preceding the starting bracket of the block tail is a new line followed by optional white spaces, the template body ends before the last new line character preceding its tail.

Static Text

We need to define the concept of line relevance to properly identify these boundaries. For this purpose, we will describe as "white spaces" the white space characters contained in a static text, whatever their position in the text.

A line is considered "relevant" if it contains anything else than white spaces, block head, block tail and comment. Note, however, that lines consisting of white spaces *only* are also considered relevant.

- If a static text is entirely located on a non relevant line, it does not produce any text.

- If a static text starts on a non relevant line, all characters located on this line are ignored and the static text is considered to start with the character after its very first new line character.

- If a static text ends on a non relevant line, all characters located on this line are ignored and the static text is considered to end with the character before its very last new line character.

- Special handling of static text following a protected area block: all white spaces following a protected area tail are retained, including the new line character. The static text then starts right after the closing bracket of the protected area tail.

Rules

Considering the boundaries outlined in section `Identifying Body Element Boundaries`_ above, the text production rules stand as follows:

- The text produced by the execution of expressions is output as is; - The text produced by the execution of static text is output as is;

-Comments do not produce any text; - Each line of the text produced by a template invocation will be indented to match the indentation of the line sporting the invocation;

-The text produced by the execution of embedded blocks, be they multi-line blocks or single line blocks, is output as is along with all text produced by the surrounding body elements.

- The text produced by the execution of stand-alone, single line blocks is output as is. White spaces located before and after the block are retained;

- The text produced by the execution of stand-alone, multi-line blocks will be output as is considering the aforementioned boundaries: if the very first character of the block body is a new line, it is ignored. Please note that if a stand-alone, multi-line block doesn't produce any text, not even a new line character will be present in the resulting text.

Examples

In the following examples, invisible characters have been materialized:

  • |inter| indicates a space character
  • |tab| indicates a horizontal tab character
  • |return| indicates a carriage return

Blocks

Embedded Blocks

The Acceleo code:

 @Some@ |inter| @text@ |inter| ``[for`` |inter| @(Sequence{false,@ |inter|
 ``false,`` |inter| ``false})`` |inter| @separator@ |inter| @('@ |inter|
 ``-`` |inter| @')]output[/for]@

produces the following result:

 @Some@ |inter| @text@ |inter| @output@ |inter| @-@ |inter| @output@
 |inter| @-@ |inter| @output@
 

The Acceleo code:

 ``[if`` |inter| @(true)]output[/if]@ |inter| @and@ |inter| @some@
 |inter| @text@

produces:

 @output@ |inter| @and@ |inter| @some@ |inter| @text@

The Acceleo code:

 |tab| ``[for`` |inter| ``(Sequence{false,`` |inter| @false})]@ |inter|
 @[self/][/for]@ |inter| @and@ |inter| @some@ |inter| @text@

produces:

 |tab| |inter| @false@ |inter| @false@ |inter| @and@ |inter| @some@
 |inter| @text@

The Acceleo code:

 ``text[for`` |inter| ``(Sequence{false,`` |inter| @false})]@ |return|
 |tab| @[self/]@ |return|
 @[/for]text@

produces:

 @text@ |tab| @false@ |return|
 |tab| @false@ |return|
 @text@

The Acceleo code:

 ``text[for`` |inter| ``(Sequence{false,`` |inter| @false})]@ |return|
 |tab| @output[/for]text@

produces:

 @text@ |tab| @output@ |tab| @outputtext@ |return|

Stand-alone single-line blocks

The Acceleo code:

 ``[for`` |inter| ``(Sequence{false,`` |inter| @false,@ |inter|
 @false})][self/][/for]@

produces:

 @falsefalsefalse@

The Acceleo code:

 ``[if`` |inter| @(true)]output[/if]@

produces:

 @output@

The Acceleo code:

 |tab| ``[for`` |inter| ``(Sequence{false,`` |inter| @false,@ |inter|
 @false})][self/][/for]@

produces:

 |tab| @falsefalsefalse@

The Acceleo code:

 ``[/if]`` |tab| |tab| ``[if`` |inter| @(true)]output[/if]@

produces:

 |tab| |tab| @output@

The Acceleo code:

 ``[/if]`` |inter| ``[comment .../]`` |tab| ``[if`` |inter| @(true)]output[/if]@

produces:

 |inter| |tab| @output@

Stand-alone multi-line blocks

The Acceleo code:

 ``[for`` |inter| ``(Sequence{false,`` |inter| ``false,`` |inter| @false})]@ |return|
 |tab| @[self/]@ |return|
 @[/for]@

produces:

 |tab| @false@ |return|
 |tab| @false@ |return|
 |tab| @false@ |return|

The Acceleo code:

 ``[if`` |inter| @(false)]output@ |return|
 @[/if]@

produces nothing, neither whitespace nor empty line.

The Acceleo code:

 ``[if`` |inter| @(true)]@ |return|
 |tab| @output[/if]@

produces:

 |tab| @output@

The Acceleo code:

 ``[comment]for`` |inter| @loop[/comment][for@ |inter|
 ``(Sequence{false,`` |inter| @false})]@ |return|
 |tab| ``[if`` |inter| @(self)]@ |return|
 |tab| |tab| @[self/]@ |return|
 |tab| @[/if]@ |return|
 @[/for]@

produces nothing, neither whitespace nor empty line.

The Acceleo code:

 |tab| ``[for`` |inter| ``(Sequence{false,`` |inter| @false,@ |inter|
 @false})]@ |return|
 @[self/]@ |return|
 |tab| @[/for]@ |return|


produces:

 @false@ |return|
 @false@ |return|
 @false@ |return|


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