Interpreter for the following language:

• expr ::= expr op expr | atom | + atom | - atom
• atom ::= (expr) | identifier | { expr, expr } | number | map(expr, identifier -> expr) | reduce(expr, expr, identifier identifier -> expr)
• op ::= + | - | * | / | ^
• stmt ::= var identifier = expr | out expr | print "string"
• program ::= stmt | program stmt

How to build and run (using Maven)

• cd to the project folder
• mvn install
• mvn exec:java

Interpreter requirements

• Interpreter should report parsing errors and mismatched types errors (adding number to a sequence, applying map/reduce to a number, etc).
• Support of calculations on long sequences (millions of elements)
• Map/reduce should be executed in parallel using rational execution strategy

UI requirements

• Program should be interpreted on the fly
• Time-consuming calculations should not block the UI and should be cancellable
• Errors from the interpreter should be shown in the editor

Dependencies

• ANTLR4 for lexer/parser
• RSyntaxTextArea for editor
• JUnit for tests