Class: Mirah::AST::Rescue

Inherits:
Node
  • Object
show all
Defined in:
lib/mirah/ast/flow.rb,
lib/mirah/compiler/flow.rb,
lib/mirah/jvm/source_generator/precompile.rb

Instance Attribute Summary

Attributes inherited from Node

#children, #inferred_type, #newline, #parent, #position

Instance Method Summary collapse

Methods inherited from Node

#<<, ===, #[], #[]=, #_dump, _load, #_set_parent, child, child_name, #child_nodes, #each, #empty?, #inferred_type!, #initialize_copy, #insert, #inspect, #inspect_children, #line_number, #log, #precompile, #resolve_if, #resolved!, #resolved?, #simple_name, #string_value, #temp, #to_s, #top_level?, #validate_child, #validate_children

Constructor Details

#initialize(parent, position, &block) ⇒ Rescue

Returns a new instance of Rescue.



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# File 'lib/mirah/ast/flow.rb', line 321

def initialize(parent, position, &block)
  super(parent, position, &block)
end

Instance Method Details

#compile(compiler, expression) ⇒ Object 



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# File 'lib/mirah/compiler/flow.rb', line 92

def compile(compiler, expression)
  compiler.line(line_number)
  compiler.rescue(self, expression)
rescue Exception => ex
  raise Mirah::InternalCompilerError.wrap(ex, self)
end

#expr?(compiler) ⇒ Boolean

Returns:



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# File 'lib/mirah/jvm/source_generator/precompile.rb', line 188

def expr?(compiler)
  false
end

#infer(typer, expression) ⇒ Object 



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# File 'lib/mirah/ast/flow.rb', line 325

def infer(typer, expression)
  unless resolved?
    # TODO: generalize this s.t.
    # the problem with deferred inference
    # assuming expression == true is dealt with
    @expression = expression if @expression == nil
    expression = @expression
    
    primary_type = if else_node
      typer.infer(body, false) if body
      typer.infer(else_node, expression)
    elsif body
      typer.infer(body, expression)
    end
    
    clause_types = clauses.map {|c| typer.infer(c, expression)}
    types = []
    types << primary_type if primary_type
    types += clause_types
    if types.any? {|t| t.nil?}
      typer.defer(self)
    else
      if !expression || clause_types.all?{ |t| primary_type.compatible? t}
        resolved!
        types.each do |type|
          @inferred_type ||= type unless type.unreachable?
        end
        @inferred_type ||= primary_type
      else
        clause, clause_type = clauses.zip(clause_types).find{ |clause, t| !primary_type.compatible? t }
        
        raise Mirah::Typer::InferenceError.new("rescue statement with incompatible result types #{primary_type} and #{clause_type}", clause)
      end
    end
  end
  @inferred_type
end