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CS269: HW/SW Engineering of Embedded Systems, Winter02
Abstract syntax trees
• An abstract syntax tree (AST) represents how a program has been derived from the grammar.
–The nodes of the AST represent productions of the grammar
–The leaves of the AST represent the terminal symbols
CompileUnit:        PackageDeclarationopt 
                    ImportDeclarationsopt 
                    TypeDeclarationsopt
PackageDeclaration: package Name ;
Name:               IDENTIFIER
    |               Name . IDENTIFIER
java
lang
package
;
.
Name
Name
CompileUnit
PackageDeclaration
...