Dr. Dobb's Journal - November 2007 - (Page 48) d11vaugh_p5db 9/17/07 8:36 AM Page 48 All objects in JavaScript are implemented as associative arrays continued from page 45 concerns and restores cohesion, while conserving the benefits of loading on demand, thus yielding the JavaScript equivalent of DLLs; see Listing Four. After calling the library-loader, the proxy restores the reference in the owner-object to its original value. This precludes needless performance-degradation subsequently, thus ensuring that we pay only for what we use. Note also that the proxy completes this step before invoking the interceptee, otherwise recursive calls would cause it to reexecute redundantly. Furthermore, note that JavaScript functions are objects in the “class” sense, and support a method called “call.” Using this, the proxy can pass its arguments array to the original function, thus passing on any arguments supplied by the interceptee’s caller and preserving transparency. Optimum Implementation This technique can be generalized to allow the arbitrary interception and loading of methods and libraries respectively, and employing a function that contains an inner function is the optimum approach here. In this scheme, the outer function takes arguments denoting the interceptee, its owner-object, and the name of the library to be loaded; on execution, it replaces the interceptee-reference in the owner-object with a reference to the inner function. This forms a closure (and what a superb use for those exotic creatures) that makes the outer function’s parameters available to the inner function when it executes. It follows that calling the interceptee invokes the inner function, which calls the library-loader before replacing the reference to itself with the original reference to 48 Dr. Dobb’s Journal l www.ddj.com l November 2007 http://www.faircom.com/go/?usesDLD http://www.faircom.com/go/?usesDLD http://www.ddj.com
Table of Contents Feed for the Digital Edition of Dr. Dobb's Journal - November 2007 Contents Hmmmm Alia Vox Developer Diaries Developer’s Notebook Smart Compilers - But Smart Enough? Conversations Grid-Enabling Resource-Intensive Applications Distributed Computing: Windows and Linux Adobe AIR: Desktop/Web Convergence Transparency on Demand Reusable Associations Effective Concurrency The Agile Edge Swaine’s Flames Dr. Dobb's Journal - November 2007 Dr. Dobb's Journal - November 2007 - (Page Cover1) Dr. Dobb's Journal - November 2007 - (Page Cover2) Dr. Dobb's Journal - November 2007 - (Page 1) Dr. Dobb's Journal - November 2007 - (Page 2) Dr. Dobb's Journal - November 2007 - (Page 3) Dr. Dobb's Journal - November 2007 - Contents (Page 4) Dr. Dobb's Journal - November 2007 - Contents (Page 5) Dr. Dobb's Journal - November 2007 - Hmmmm (Page 6) Dr. Dobb's Journal - November 2007 - Hmmmm (Page 7) Dr. Dobb's Journal - November 2007 - Hmmmm (Page 8) Dr. Dobb's Journal - November 2007 - Hmmmm (Page 9) Dr. Dobb's Journal - November 2007 - Alia Vox (Page 10) Dr. Dobb's Journal - November 2007 - Alia Vox (Page 11) Dr. Dobb's Journal - November 2007 - Developer Diaries (Page 12) Dr. Dobb's Journal - November 2007 - Developer Diaries (Page 13) Dr. Dobb's Journal - November 2007 - Developer’s Notebook (Page 14) Dr. Dobb's Journal - November 2007 - Developer’s Notebook (Page 15) Dr. Dobb's Journal - November 2007 - Smart Compilers - But Smart Enough? (Page 16) Dr. Dobb's Journal - November 2007 - Smart Compilers - But Smart Enough? (Page 17) Dr. Dobb's Journal - November 2007 - Smart Compilers - But Smart Enough? (Page 18) Dr. Dobb's Journal - November 2007 - Smart Compilers - But Smart Enough? (Page 19) Dr. Dobb's Journal - November 2007 - Conversations (Page 20) Dr. Dobb's Journal - November 2007 - Conversations (Page 21) Dr. Dobb's Journal - November 2007 - Grid-Enabling Resource-Intensive Applications (Page 22) Dr. Dobb's Journal - November 2007 - Grid-Enabling Resource-Intensive Applications (Page 23) Dr. Dobb's Journal - November 2007 - Grid-Enabling Resource-Intensive Applications (Page 24) Dr. Dobb's Journal - November 2007 - Grid-Enabling Resource-Intensive Applications (Page 25) Dr. Dobb's Journal - November 2007 - Grid-Enabling Resource-Intensive Applications (Page 26) Dr. Dobb's Journal - November 2007 - Grid-Enabling Resource-Intensive Applications (Page 27) Dr. Dobb's Journal - November 2007 - Grid-Enabling Resource-Intensive Applications (Page 28) Dr. Dobb's Journal - November 2007 - Grid-Enabling Resource-Intensive Applications (Page 29) Dr. Dobb's Journal - November 2007 - Distributed Computing: Windows and Linux (Page 30) Dr. Dobb's Journal - November 2007 - Distributed Computing: Windows and Linux (Page 31) Dr. Dobb's Journal - November 2007 - Distributed Computing: Windows and Linux (Page 32) Dr. Dobb's Journal - November 2007 - Distributed Computing: Windows and Linux (Page 33) Dr. Dobb's Journal - November 2007 - Distributed Computing: Windows and Linux (Page 34) Dr. Dobb's Journal - November 2007 - Distributed Computing: Windows and Linux (Page 35) Dr. Dobb's Journal - November 2007 - Adobe AIR: Desktop/Web Convergence (Page 36) Dr. Dobb's Journal - November 2007 - Adobe AIR: Desktop/Web Convergence (Page 37) Dr. Dobb's Journal - November 2007 - Adobe AIR: Desktop/Web Convergence (Page 38) Dr. Dobb's Journal - November 2007 - Adobe AIR: Desktop/Web Convergence (Page 39) Dr. Dobb's Journal - November 2007 - Adobe AIR: Desktop/Web Convergence (Page 40) Dr. Dobb's Journal - November 2007 - Adobe AIR: Desktop/Web Convergence (Page 41) Dr. Dobb's Journal - November 2007 - Transparency on Demand (Page 42) Dr. Dobb's Journal - November 2007 - Transparency on Demand (Page 43) Dr. Dobb's Journal - November 2007 - Transparency on Demand (Page 44) Dr. Dobb's Journal - November 2007 - Transparency on Demand (Page 45) Dr. Dobb's Journal - November 2007 - Transparency on Demand (Page 46) Dr. Dobb's Journal - November 2007 - Transparency on Demand (Page 47) Dr. Dobb's Journal - November 2007 - Transparency on Demand (Page 48) Dr. Dobb's Journal - November 2007 - Transparency on Demand (Page 49) Dr. Dobb's Journal - November 2007 - Transparency on Demand (Page 50) Dr. Dobb's Journal - November 2007 - Reusable Associations (Page 51) Dr. Dobb's Journal - November 2007 - Reusable Associations (Page 52) Dr. Dobb's Journal - November 2007 - Reusable Associations (Page 53) Dr. Dobb's Journal - November 2007 - Reusable Associations (Page 54) Dr. Dobb's Journal - November 2007 - Reusable Associations (Page 55) Dr. Dobb's Journal - November 2007 - Reusable Associations (Page 56) Dr. Dobb's Journal - November 2007 - Effective Concurrency (Page 57) Dr. Dobb's Journal - November 2007 - Effective Concurrency (Page 58) Dr. Dobb's Journal - November 2007 - Effective Concurrency (Page 59) Dr. Dobb's Journal - November 2007 - The Agile Edge (Page 60) Dr. Dobb's Journal - November 2007 - The Agile Edge (Page 61) Dr. Dobb's Journal - November 2007 - The Agile Edge (Page 62) Dr. Dobb's Journal - November 2007 - The Agile Edge (Page 63) Dr. Dobb's Journal - November 2007 - Swaine’s Flames (Page 64) Dr. Dobb's Journal - November 2007 - Swaine’s Flames (Page Cover3) Dr. Dobb's Journal - November 2007 - Swaine’s Flames (Page Cover4)
For optimal viewing of this digital publication, please enable JavaScript and then refresh the page. If you would like to try to load the digital publication without using Flash Player detection, please click here.