License	GNU LGPLv3
Maintainer	paul.bittner@uni-ulm.de
Safe Haskell	Safe

SimpleJava

Description

Example implementation of a context free grammar. This example represents a simplified subset of the Java programming language. It contains the Grammar implementation as well as functions to construct an AST in this sub-language.

Synopsis

data SimpleJavaGrammar
- = SJava_MethodDef
- | SJava_ParametersDef
- | SJava_Args
- | SJava_Statements
- | SJava_ExprStatement
- | SJava_Assignment
- | SJava_Return
- | SJava_Condition
- | SJava_FuncCall
- | SJava_Expression
- | SJava_UnaryOp
- | SJava_BinaryOp
- | SJava_VarDecl
- | SJava_VarRef
- | SJava_Literal
- | SJava_Type
- | SJava_File
type SJavaAST a = AST SimpleJavaGrammar a
type SSJavaAST = SJavaAST String
type SJavaState = Tree (State UUID (Node SimpleJavaGrammar String))
sjava_methoddef :: String -> String -> [(String, String)] -> [SJavaState] -> SJavaState
sjava_parametersdef :: [(String, String)] -> SJavaState
sjava_args :: [SJavaState] -> SJavaState
sjava_statements :: [SJavaState] -> SJavaState
sjava_exprstatement :: SJavaState -> SJavaState
sjava_assignment :: SJavaState -> String -> SJavaState -> SJavaState
sjava_return :: SJavaState -> SJavaState
sjava_condition :: SJavaState -> [SJavaState] -> SJavaState
sjava_funccall :: String -> [SJavaState] -> SJavaState
sjava_expr :: SJavaState -> SJavaState
sjava_unaryop :: String -> SJavaState -> SJavaState
sjava_binaryop :: SJavaState -> String -> SJavaState -> SJavaState
sjava_vardecl :: String -> String -> SJavaState
sjava_varref :: String -> SJavaState
sjava_literal :: String -> SJavaState
sjava_type :: String -> SJavaState
sjava_file :: String -> [SJavaState] -> SJavaState

Documentation

data SimpleJavaGrammar Source #

Simplified subset of the Java grammar.

Constructors

SJava_MethodDef	Rule for method definitions.
SJava_ParametersDef	Rule for a parameters list (e.g., in a method declaration).
SJava_Args	Rule for arguments passed to a method call (e.g., `(1 + 2, "arg2", null)`).
SJava_Statements	Rule for a sequential list of statements (e.g., inside a method).
SJava_ExprStatement	Rule for a statement that is a single expression (e.g., `x += 3` that also returns the new value of `x` is an expression statement).
SJava_Assignment	Rule for assignments of variables (e.g., `x = 3`).
SJava_Return	Rule for `return` statements.
SJava_Condition	Rule for conditions (`if`).
SJava_FuncCall	Rule for function calls.
SJava_Expression	Rule for expressions (e.g., `1 + 1`).
SJava_UnaryOp	Rule for unary operations (e.g., `!` or `-`).
SJava_BinaryOp	Rule for binary operations (e.g., `+` or `*`).
SJava_VarDecl	Rule for variable declarations (e.g., `int x;`).
SJava_VarRef	Rule for variable references.
SJava_Literal	Rule for literals.
SJava_Type	Rule for types (e.g., `int` in `int x;`).
SJava_File	Rule that represents an entire file. Usually the root of the AST.

Instances

Instances details

Eq SimpleJavaGrammar Source #
Instance details Defined in SimpleJava Methods (==) :: SimpleJavaGrammar -> SimpleJavaGrammar -> Bool (/=) :: SimpleJavaGrammar -> SimpleJavaGrammar -> Bool
Show SimpleJavaGrammar Source #
Instance details Defined in SimpleJava Methods showsPrec :: Int -> SimpleJavaGrammar -> ShowS show :: SimpleJavaGrammar -> String showList :: [SimpleJavaGrammar] -> ShowS
Grammar SimpleJavaGrammar Source #	Define optionality for all node types in our Java grammar
Instance details Defined in SimpleJava Methods nodetypeof :: SimpleJavaGrammar -> NodeType Source #
ASTPrettyPrinter SimpleJavaGrammar Source #
Instance details Defined in SimpleJava Methods prettyPrint :: Monoid b => b -> (Node SimpleJavaGrammar a -> Int -> b) -> (Node SimpleJavaGrammar a -> String -> b) -> (Node SimpleJavaGrammar a -> b) -> AST SimpleJavaGrammar a -> b Source #

type SJavaAST a = AST SimpleJavaGrammar a Source #

An AST build from the SimpleJavaGrammar.

type SSJavaAST = SJavaAST String Source #

An AST build from the SimpleJavaGrammar containing Strings as values.

type SJavaState = Tree (State UUID (Node SimpleJavaGrammar String)) Source #

A SSJavaAST whose nodes are not yet assigned their UUIDs (they are still states waiting for evaluation).

sjava_methoddef :: String -> String -> [(String, String)] -> [SJavaState] -> SJavaState Source #

Construct a method definition with given (1) return type, (2) name, (3) parameters (pairs of type and name), and (4) the given content (list of statements).

sjava_parametersdef :: [(String, String)] -> SJavaState Source #

Construct a definition of parameters subtree from the given pairs of type and name.

sjava_args :: [SJavaState] -> SJavaState Source #

Construct an arguments subtree from the given list of subtrees (e.g., (1 + 2, "arg2", null)).

sjava_statements :: [SJavaState] -> SJavaState Source #

Construct a statements block from a list of statements.

sjava_exprstatement :: SJavaState -> SJavaState Source #

Wrap the given subtree in an expression statement. The given tree should be an expression. Pseudocode example: sjava_exprstatement 'x = 3 == 'x + 3;'.

sjava_assignment :: SJavaState -> String -> SJavaState -> SJavaState Source #

Constructs an assignment where parameter

represents the left side of the assignment (e.g., a variable that should be assigned a value),
is the operator's name to use (e.g., "="), and
is the expression to assign (e.g. "1 + 2").

sjava_return :: SJavaState -> SJavaState Source #

Constructs a return statement that returns the given expression.

sjava_condition :: SJavaState -> [SJavaState] -> SJavaState Source #

Constructs an if-block (without else case) with the given condition (first argument) and sequence of statements to run when the condition is met.

sjava_funccall :: String -> [SJavaState] -> SJavaState Source #

Constructs a call to a function the given name and a list of arguments to pass.

sjava_expr :: SJavaState -> SJavaState Source #

Wraps an tree in an expression. For example, a literal is an expression. Thus a literal can be used anywhere an expression required but should be wrapped into an expression first.

sjava_unaryop :: String -> SJavaState -> SJavaState Source #

Constructs a unary operation (e.g. -3) from a given name (-) that is applied to the given expression (3).

sjava_binaryop :: SJavaState -> String -> SJavaState -> SJavaState Source #

Constructs a binary operator from a given name and two expressions.

sjava_vardecl :: String -> String -> SJavaState Source #

Constructs a variable declaration (e.g., int x;) from a type (e.g., int) and a name (e.g., x).

sjava_varref :: String -> SJavaState Source #

Constructs a reference to a variable with the given name. The returned tree is a leaf.

sjava_literal :: String -> SJavaState Source #

Constructs a literal with the given name. The returned tree is a leaf.

sjava_type :: String -> SJavaState Source #

Constructs a type with the given name. The returned tree is a leaf.

sjava_file :: String -> [SJavaState] -> SJavaState Source #

Constructs a file with the given name and content.