IR Expression Nodes
Expressions compute a value based on an operation and one or more values. Exp Nodes represent this. There are a lot of expressions with wide ranging effects.
Literals (integer constants, strings) are also expressions.
An expression may or may not have a side effect depending on the operation, and what is being operated on.
The expression nodes are mostly flat. Expressions contain other expressions, but generally not a specific kind.
Classes
| Exp | Base class for all expressions. |
| LiteralExp | Base class for literal expressions. |
| Ternary | A ternary expression is a shorthand if statement in the form of an expression. |
| BinOp | A BinOp is an operation the operates on two expressions with a given operation. |
| Unary | A Unary operation is prepended to the back of an expression. |
| Postfix | A postfix operation is appended to an expression. |
| PropertyExp | A looked up postfix operation is appended to an expression. |
| Constant | A Constant is a literal value of a given type. |
| ArrayLiteral | Represents an array literal. Contains a list of expressions with (if semantically sound) a common type. |
| AssocArray | Represents an associative array literal -- a list of key/value pairs. |
| IdentifierExp | Represents a single identifier. Replaced with ExpReference in a pass. |
| Assert | An Assert checks that a condition is true, and dies with an optional message if not. |
| StringImport | A StringImport creates a string literal from a file on disk at compile time. |
| Typeid | The typeid expression returns the typeinfo of a given type or expression. |
| IsExp | The is expression is a bit of a swiss army knife. It can be simply used to determine whether a given type is well-formed, or if a given type is a certain other type, or can be converted into another type. |
| FunctionLiteral | A function literal can define a normal function, or a delegate (a function with context). There are multiple ways to define these but the long hand way is int function(int a, int b) { return a + b; } Defines a function that takes two integers and returns them added up. int delegate(int a, int b) { return a + b + c; } Is the same, except it has access to the outer scope's variables. |
| ExpReference | An ExpReference replaces chained postfix look ups with the result of the lookup. A cache that is inserted later, in other words. |
| TypeExp | A TypeExp is used when a primitive type is used in an expression. This is currently limited to .max/min and (void*).max/min. |
| StoreExp | A StoreExp is used when a NamedType is used in an expression within a WithStatement, like so: with (Class.Enum) { int val = DeclInEnum; }. |
| StatementExp | A StatementExp is a internal expression for inserting statements into a expression. Note that this is not a function and executes the statements just as if they where inserted in the BlockStatement that the StatementExp is in. Meaning any ReturnStatement will return the current function not this StatementExp. |
| TokenExp | Expression that corresponds to what was once special tokens. FUNCTION, PRETTY_FUNCTION, FILE, and __LINE. |
| VaArgExp | Expression that assists in working with varargs. |
| AccessExp | An expression that represents a simple identifier.identifier lookup. |
| RunExp | An expression that forces the compiler to evaluate another expression at compile time. |
| ComposableString | A string that contains expressions to be formatted inline. |