define switch statement

2 files changed, 21 insertions, 1 deletions

diff --git a/language/statements/index.rst b/language/statements/index.rst
index 38bfbb1..e0a0a37 100644
--- a/language/statements/index.rst
+++ b/language/statements/index.rst
@@ -12,7 +12,7 @@ Statements
 
     When a block is executed, each of the containing statements, in linear order, is executed.
 
-.. crowbar:element:: Statement <- VariableDefinition / StructureStatement / FlowControlStatement / AssignmentStatement / FragileStatement / ExpressionStatement
+.. crowbar:element:: Statement <- VariableDefinition / StructureStatement / FlowControlStatement / AssignmentStatement / FragileStatement / ExpressionStatement / EmptyStatement
 
     Crowbar has many different types of statement.
 
diff --git a/language/statements/structure.rst b/language/statements/structure.rst
index 9330bf6..1a412af 100644
--- a/language/statements/structure.rst
+++ b/language/statements/structure.rst
@@ -19,3 +19,23 @@ Structure Statements
     First, the expression is evaluated.
     If the expression evaluates to a ``bool`` value of ``true``, then the first block will be executed.
     If the expression evaluates to a ``bool`` value of ``false``, either the second block is executed or nothing is executed.
+
+.. crowbar.element.. SwitchStatement <- 'switch' '(' Expression ')' '{' (CaseSpecifier / Statement)+ '}'
+                     CaseSpecifier <- 'case' Expression ':' / 'default' ':'
+
+    A switch statement allows many different actions to be taken depending on the value of some expression.
+
+    Compile-time Behavior:
+
+    The expression must have a type which is either some integer type or an enum.
+    The expression in a case specifier must have a value which can always be known at compile time, i.e. its value must be a constant or computed from only constants.
+    Either there must be a case specifier for every valid value in the type of the switch expression, or there must be a default case specifier.
+    At most one default case may be present.
+
+    Runtime Behavior:
+
+    First, the switch expression is evaluated.
+    Whichever case specifier has the same value, or the default case specifier if none is found, is then selected as the matching case specifier.
+    Any case specifiers immediately following the matching case specifier is ignored.
+    Subsequent statements are then executed, in linear order, until another case specifier is reached.
+    The execution of the switch statement then ends.