[docs] Update documentation on assert for its enabling and disabling.

close #820

Signed-off-by: Stéphane Galland <galland@arakhne.org>

docs/io.sarl.docs.markdown/src/main/documentation/reference/general/Assertion.md

@@ -57,6 +57,46 @@ The message string follows the condition, with a coma character between them.
 				}
 			}
 		[:End:]
+		
+# Enable and Disable Assertions.
+
+By default, assertions are disabled. It means that they are not evaluated at run-time.
+In this way, if someone is launching your application, the application is running quickly, and
+the assert errors cannot occur. It is compliant with the fact that assertions are tests by and for
+the application's developers: the final user of the application is not care about the implementation
+constraints.
+
+For enabling and disabling the assertions, you must change the launch configuration within the SARL product,
+or use an option that is provided by the SARL run-time environment.
+
+## Inside the SARL Development Environment
+
+Within the SARL development environment, you must define a launch configuration for running a SARL application.
+Two launch configurations are available:
+* "SARL Agent" for launching an agent, and
+* "SARL Application" for launching a standard application (based on the definition of a `main` method), which will launch the SARL framework later. 
+
+Both of these launch configurations allow you to enable or disable the assertions.
+On the figure below, you could see the "Enable assertions in run mode" and "Enable assertions in debug mode"
+checkboxes within the "Launch Options" section.
+If the first (resp. second) box is checked, assertions will be enabled when you application was launched in run (resp. debug) mode. 
+
+![Screenshot of the dialog box of a SARL launch configuration](./enableassertions.png)
+
+## Launching the Janus framework 
+
+The Janus framework is one implementation of a SARL run-time environment. You have to use one of its command-line
+options for enabling assertions. All the command-line options are detailed on a [dedicated page](../../tools/Janus.md).
+Usually, the option for enabling the assertions is the same as the one of the Java virtual machine: [:shorteaopt!].
+
+## Launching the Java virtual machine 
+
+If you want to run your SARL application by launching the Java virtual machine, you could use the standard command
+line options [:longeaopt:] and [:shorteaopt:] that are provided by this virtual machine:
+
+		java [ [:longeaopt](-enableassertions) | [:shorteaopt](-ea)  ] <class name>
+
+
 
 [:Include:](../generalsyntaxref.inc)
 

main/targetplatform/io.sarl.lang.targetplatform.target

@@ -36,8 +36,8 @@
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