| 1 | // | 
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| 2 | // Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo | 
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| 3 | // | 
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| 4 | // The contents of this file are covered under the licence agreement in the | 
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| 5 | // file "LICENCE" distributed with Cforall. | 
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| 6 | // | 
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| 7 | // Occurs.cc -- | 
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| 8 | // | 
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| 9 | // Author           : Richard C. Bilson | 
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| 10 | // Created On       : Sun May 17 09:47:41 2015 | 
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| 11 | // Last Modified By : Peter A. Buhr | 
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| 12 | // Last Modified On : Sun May 17 09:49:26 2015 | 
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| 13 | // Update Count     : 2 | 
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| 14 | // | 
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| 15 |  | 
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| 16 | #include <set>                // for set, _Rb_tree_const_iterator | 
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| 17 | #include <string>             // for string | 
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| 18 |  | 
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| 19 | #include "SynTree/Type.h"     // for TypeInstType, Type | 
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| 20 | #include "SynTree/Visitor.h"  // for Visitor | 
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| 21 | #include "TypeEnvironment.h"  // for EqvClass, TypeEnvironment | 
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| 22 |  | 
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| 23 | namespace ResolvExpr { | 
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| 24 | class Occurs : public Visitor { | 
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| 25 | public: | 
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| 26 | Occurs( std::string varName, const TypeEnvironment &env ); | 
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| 27 | bool get_result() const { return result; } | 
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| 28 | virtual void visit( TypeInstType *typeInst ); | 
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| 29 | private: | 
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| 30 | bool result; | 
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| 31 | std::set< std::string > eqvVars; | 
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| 32 | const TypeEnvironment &env; | 
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| 33 | }; | 
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| 34 |  | 
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| 35 | bool occurs( Type *type, std::string varName, const TypeEnvironment &env ) { | 
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| 36 | Occurs occur( varName, env ); | 
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| 37 | type->accept( occur ); | 
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| 38 | return occur.get_result(); | 
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| 39 | } | 
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| 40 |  | 
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| 41 | Occurs::Occurs( std::string varName, const TypeEnvironment &env ) : result( false ), env( env ) { | 
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| 42 | EqvClass eqvClass; | 
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| 43 | if ( env.lookup( varName, eqvClass ) ) { | 
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| 44 | eqvVars = eqvClass.vars; | 
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| 45 | } else { | 
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| 46 | eqvVars.insert( varName ); | 
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| 47 | } // if | 
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| 48 | } | 
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| 49 |  | 
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| 50 | void Occurs::visit( TypeInstType *typeInst ) { | 
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| 51 | EqvClass eqvClass; | 
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| 52 | ///   std::cout << "searching for vars: "; | 
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| 53 | ///   std::copy( eqvVars.begin(), eqvVars.end(), std::ostream_iterator< std::string >( std::cout, " " ) ); | 
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| 54 | ///   std::cout << std::endl; | 
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| 55 | if ( eqvVars.find( typeInst->get_name() ) != eqvVars.end() ) { | 
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| 56 | result = true; | 
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| 57 | } else if ( env.lookup( typeInst->get_name(), eqvClass ) ) { | 
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| 58 | if ( eqvClass.type ) { | 
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| 59 | ///       std::cout << typeInst->get_name() << " is bound to"; | 
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| 60 | ///       eqvClass.type->print( std::cout ); | 
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| 61 | ///       std::cout << std::endl; | 
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| 62 | eqvClass.type->accept( *this ); | 
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| 63 | } // if | 
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| 64 | } // if | 
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| 65 | } | 
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| 66 | } // namespace ResolvExpr | 
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| 67 |  | 
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| 68 | // Local Variables: // | 
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| 69 | // tab-width: 4 // | 
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| 70 | // mode: c++ // | 
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| 71 | // compile-command: "make install" // | 
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| 72 | // End: // | 
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