FUNCTIONAL                                                                                                     Many of these notes are based on 
                                                                                                                                                                    
                                    PROGRAMMING AND                                                                                                                “Haskell: The Craft of Functional 
                                                           HASKELL                                                                                                 Programming”, Simon Thompson, Addison-
                                                                                                                                                                   Wesley, 1996 
                                                                                                                                                                    
                                                                                                                                                                   This introduction is based on chapter one of: 
                                                  SOME ELEMENTARY NOTES                                                                                             
                                                                                                                                                                   “Functional Programming with Miranda”, 
                                                                                
                                                                                                                                                                   Ian Holyer, UCL Press, 1993 
                                                                                                                                                                    
                                                                 Steve Reeves                                                                                      which is in the Library. 
                                             Department of Computer Science 
                                                         University of Waikato                                                                                     Other good books, all in the Library, on functional 
                                                                                                                                                                   programming are: 
                                                                                                                                                                    
                                                                                                                                                                   “Miranda: The Craft of Functional 
                                                                                                                                                                   Programming”, Simon Thompson, Addison-
                                                                                                                                                                   Wesley, 1995 
                                                                                                                                                                    
                                                                                                                                                                   “Introduction to Functional Programming”, 
                                                                                                                                                                   Richard Bird and Philip Wadler, Prentice-
                                                                                                                                                                   Hall, 1988 
                                                                                                                                                                    
                                                                                                                                                                   “Elements of Functional Programming”, 
                                                                                                                                                                   Chris Reade, Addison-Wesley, 1989 
                                                                                                                                                                    
                    Functional Programming  and Haskell–Steve Reeves–2006–University of Waikato                       1                                            Functional Programming  and Haskell–Steve Reeves–2006–University of Waikato                       2 
                    Also, search the Library catalogues for “functional                                                                                             
                    programming” - there are about 12 more books on the                                                                                            Taxonomy 
                    subject in our Library
                                                                                                                                                                    
                                                                                                                                                                    
                                                                                                                                                                                                                                                                         
                                                                                                                                                                                            specification 
                                                                                                                                                                    
                                                                                                                                                                    
                                                                                                                                                                    
                                                                                                                                                                                                     declarative                               logical 
                                                                                                                                                                    
                                                                                                                                                                                                                                               functional 
                                                                                                                                                                    
                                                                                                                                                                   languages 
                                                                                                                                                                    
                                                                                                                                                                                                                                               structured 
                                                                                                                                                                    
                                                                                                                                                                                                     procedural                                high-level 
                                                                                                                                                                    
                                                                                                                                                                                                                                               low-level
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                    Procedural Languages                                                                                                                                Evolution 
                                                                                                                                                                    
                    • developed first in the 1950s                                                                                                                  
                                                                                                                                                                                                                              machine code 
                    • most languages today are procedural                                                                                                            low-level 
                                                                                                                                                                    
                    • two common ideas                                                                                                                                                                                        assembly  
                                                                                                                                                                    
                                     -       instructions executed                                                                                                  
                                             sequentially                                                                                                           
                                                                                                                                                                                                                       
                                     -       values stored in locations                                                                                              high-level                                               ForTran, BASIC 
                                                                                                                                                                    
                    • brought together by defining sequences                                                                                                        
                        of instructions to change the contents of                                                                                                   
                        storage - procedures, routines                                                                                                              
                                                                                                                                                                     structured                                       C, Pascal, Modula 
                    these languages closely match the                                                                                                               
                        architecture of most of today!s computers                                                                                                   
                                                                                                                                                                     object-oriented                                          Smalltalk 
                                     -       advantage is efficiency                                                                                                                                                          C++ 
                                                                                                                                                                    
                                     -       disadvantage is unnecessary                                                                                            
                                     detail
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                    Declarative Languages                                                                                                                           
                                                                                                                                                                    
                                                                                                                                                                    
                    • origins in the !-calculus of 1930s                                                                                                           • Various sorts of expressions declare 
                                                                                                                                                                        relations between values 
                    • became practical in the 1970s                                                                                                                 
                                                                                                                                                                    
                    • at a higher-level than any of the                                                                                                            • Logic programming languages use 
                        procedural languages                                                                                                                            relations  
                                                                                                                                                                    
                    • breaks away from the procedural model                                                                                                         
                                                                                                                                                                   • Specification languages use any 
                    • allows expression of algorithms in a very                                                                                                         mathematical structures you like 
                        clear and direct way                                                                                                                        
                                                                                                                                                                       -            they are more general and                                                            
                    • few unnecessary details                                                                                                                             expressive than either logic of   
                                                                                                                                                                          functional languages 
                    • values can be defined and manipulated                                                                                                         
                        directly                                                                                                                                     -              so expressive that you can write  
                                                                                                                                                                          down relations that are not                                                           
                    • no need to worry about how or where                                                                                                                 computable!! 
                        they are stored                                                                                                                             
                                                                                                                                                                    
                    • algorithms are given by declaring                                                                                                            • Functional languages use functions 
                        relationships between values - no                                                                                                           
                        concern about the order used 
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