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-rw-r--r--docs/user-guide/03-convenience-features.md65
-rw-r--r--docs/user-guide/toc.html1
2 files changed, 66 insertions, 0 deletions
diff --git a/docs/user-guide/03-convenience-features.md b/docs/user-guide/03-convenience-features.md
index 5646292aa..d522daf81 100644
--- a/docs/user-guide/03-convenience-features.md
+++ b/docs/user-guide/03-convenience-features.md
@@ -793,6 +793,71 @@ by using the `[ForceInline]` decoration:
int f(int x) { return x + 1; }
```
+Error handling
+-----------------
+
+Slang supports an error handling mechanism that is superficially similar to
+exceptions in many other languages, but has some unique characteristics.
+
+In contrast to C++ exceptions, this mechanism makes the control flow of errors
+more explicit, and the performance charasteristics are similar to adding an
+if-statement after every potentially throwing function call to check and handle
+the error.
+
+In order to be able to throw an error, a function must declare the type of that
+error with `throws`:
+```
+enum MyError
+{
+ Failure,
+ CatastrophicFailure
+}
+
+int f() throws MyError
+{
+ if (computerIsBroken())
+ throw MyError.CatastrophicFailure;
+ return 42;
+}
+```
+Currently, functions may only throw a single type of error.
+
+To call a function that may throw, you must prepend it with `try`:
+
+```
+let result = try f();
+```
+
+If you don't catch the `try`, related errors are re-thrown and the calling
+function must declare that it `throws` that error type:
+
+```
+void g() throws MyError
+{
+ // This would not compile if `g()` wasn't declared to throw MyError as well.
+ let result = try f();
+ printf("Success: %d\n", result);
+}
+```
+
+To catch an error, you can use a `do-catch` statement:
+
+```
+void g()
+{
+ do
+ {
+ let result = try f();
+ printf("Success: %d\n", result);
+ }
+ catch(err: MyError)
+ {
+ printf("Not good!\n");
+ }
+}
+```
+
+You can chain multiple catch statements for different types of errors.
Special Scoping Syntax
-------------------
diff --git a/docs/user-guide/toc.html b/docs/user-guide/toc.html
index 47e0c05ad..c83f36282 100644
--- a/docs/user-guide/toc.html
+++ b/docs/user-guide/toc.html
@@ -49,6 +49,7 @@
<li data-link="convenience-features#extensions"><span>Extensions</span></li>
<li data-link="convenience-features#multi-level-break"><span>Multi-level break</span></li>
<li data-link="convenience-features#force-inlining"><span>Force inlining</span></li>
+<li data-link="convenience-features#error-handling"><span>Error handling</span></li>
<li data-link="convenience-features#special-scoping-syntax"><span>Special Scoping Syntax</span></li>
<li data-link="convenience-features#user-defined-attributes-experimental"><span>User Defined Attributes (Experimental)</span></li>
</ul>