FASTPharoBlockExpression contains a FASTPharoBlockDefinition which contains statements

maybewe could have only FASTPharoBlock like in Pharo AST ?

statement block seems unused

Some nodes are FASTPharoXYZ, others are FASTXYZ :-(

For example, a FASTExpressionStatement might contain a FASTPharoAssignementExpression or a FASTPharoMessageSend
and a FASTPharoMessageSend might contain a FASTVariableExpression

this code:

assign := FASTPharoAssignmentExpression new.
assign variable: (FASTVariableExpression new name: 'lhs').
assign expression: (FASTVariableExpression new name: 'rhs').

results in an assignment where the #variable is named 'rhs' and not 'lhs'