A1.RJS@isumvs.iastate.edu (Ricardo Salvador) (02/02/90)
Gavin C. H. Zau asks for reasons to upgrade from Turbo Pascal version 4 to version 5.5: >What are the main advantages of the new version? >Can it use extended memory? How hard is it to upgrade >existing programs - we have a lot of data aquisition programs. The main innnovation in 5.5 is the addition of object-oriented programming (OOP) features. This boils down to the addition of some keywords (OBJECT, VIRTUAL, DESTRUCTOR, CONSTRUCTOR) that enable you to encapsulate a data structure together with the procedure(s) that work on that data structure. In addition, all or some of the features of any given data structure can be "inherited" by a new data structure, so that any parent data structure can diverge into several polymorphic data structures. This kind of "smart" data structure is referred to as an object and can be of great aid in programming complex processes or events, such as a GUI for example. If you don't care about OOP, then another factor to keep in mind is that upgrade costs for future versions of TP will undoubtedly be lower if you've kept up with the upgrade path (i.e., it will be cheaper to upgrade from a recent version than from an older version). If you _are_ interested in learning more about OOP as a programing paradigm that may become universal in the near future, then you should check Dick Pountain's article in the current (February 1990) issue of BYTE. The instance of an OOP language that Mr. Pountain uses for his examples is TP 5.5. A quick reading of this should give you a good feel for OOP and give you an indication of whether the upgrade is worth it for you. In every other respect, you will find that version 4 and 5.5 are upwardly compatible. -------------------------------------------------------------------- Ricardo Salvador - Iowa State University of Science and Technology - -------------------------------------------------------------------- Asst. Professor of Agronomy +------------------------+ Computer Education Specialist | BITNET: A1.RJS@ISUMVS | for the College of Agriculture | A3.RJS@ISUMVS | 117 Curtiss Hall | A3RJS@ISUVAX | Iowa State University of | COMPUSERVE: RSalvador | Science and Technology | GEnie: R.Salvador| Ames, Iowa 50011 +------------------------+ -------------------------------------------------------------------- "Education is a journey, not a destination." --------------------------------------------------------------------
dmurdoch@watstat.waterloo.edu (Duncan Murdoch) (02/02/90)
In article <22298@adm.BRL.MIL> A1.RJS@isumvs.iastate.edu (Ricardo Salvador) writes: >Gavin C. H. Zau asks for reasons to upgrade from Turbo Pascal >version 4 to version 5.5: > >The main innnovation in 5.5 is the addition of object-oriented >programming (OOP) features. That's the main difference between 5.5 and 5, but I'd say a more significant difference between 5.5 and 4 is the integrated debugger that version 5 introduced. It alone is worth the upgrade price; if you also buy the "Professional" version, you get an external debugger which is even better (especially on a 386). They also added a floating point emulation library with 5, so that you can write programs that use the IEEE types with or without a numeric coprocessor. Other minor differences between 5.5 and 5: - improved overlay support. I've never used it, so I don't know if it really is significantly better. - eradication of a long-standing bug in floating point code generation. If e is declared extended, then you'll get an error trying to execute e:=e+e+e+e+e+e+e+e+e+e+e+e; in versions 4 and 5, but not in 5.5. Similarly for any expression involving a long string of operations on extendeds. Duncan Murdoch