Hi, Jason, From: "Jason Cunliffe" > Greetings smart people
Whoops, I guess that rules me out after all. I misread the subject as saying, "Idiots to reduce logic clutter," and I assumed I would be perfect to answer. :-) ... > Time to factor out and simplify the mess. Need strategic > advice.. or examples of rebol idioms for idioms to keep > manage logic, keep clutter in check, avoid nested 'either > [using 'find perhaps functions, objects..] ... original email: http://www.escribe.com/internet/rebol/m26449.html First, I'll throw in a few comments interspersed in the sample that you submitted to be sure that we are on the same wavelength. ... > either error? try [ > ;condition > upass: cgi-obj/userpass > ][ > ;error > if = upass "" [ We know that a form GET only returns name-value pairs where a value was supplied. At this point, I assume that cgi-obj contains the name-value pairs returned from a submitted form. What I don't know is whether the cgi-obj starts with defaults for all fields and then fills in the returned values, or is created directly by decoding and parsing the returns. In the former, then a given field will always be present; whereas, in the later case, only fields with return values will be present. Each offers opportunities for compressing the logic. Given that you are assigning upass inside a try block, I am assuming that cgi-obj only contains returned name-value pairs (otherwise an assignment error would "never" occur). If so, then if an error occurs, it is only do to cgi-object not containing the userpass path. Therefore, there may be no reason to check for: > if <> upass "" [ As an aside, I assume that the quit command was supposed to be the final line in the first if block, otherwise, one would never pass through to the second if. > ; ok user has submitted a name and password > ; check to see if they match > upass: cgi-obj/userpass Just a minor point: this assignment is redundant with the one done in the try block. Given what has been presented, I could see the following compressed version as offering similar functionality. Of course, I have no direct way to test it. ;==================================== ; TEST FOR PASSWORD ;==================================== upass: copy "" loginstatus: false either error? try [ ;condition upass: cgi-obj/userpass ][ ;error: userpass must not have existed print rejoin [ {<b>Bad login!</b>} {no user password provided } {<a href="upload.html">}{try again}{</a>} {<br>} ] quit ][ ; ok user has submitted a name and password ; check to see if they match if not loginstatus: equal? upass logindict/:uname [ ;trouble in paradise - help them out.. print rejoin [ {<br>Username and password do not match. <br>Please } {<a href="upload.html">}{try again}{</a>} {<form method="POST" action="echo-login.r" enctype="multipart/form-data"> <i>Forgot your login or need to register ? <br> Please enter your email address here: </i> <input type="text" name="email_address" value=""/> <input type="submit" value="send login by email"/> </form>} ] quit ] ] ;if program execution passes through to here, then a valid ; user name and password cobination have been offered ; and loginstatus should now be "true" ; OK to continue with processing ;======================= If this error checking script continues through a number of fields, I would likely encapsulate the error generating code into a function that allows the error issue statement to be passed as a parameter and that offers a refinement switch that allows the user to (re)register if the error warrants. error-page: func [ err-mess [string!] /register ][ print rejoin [ {<br>} err-mess {<br>Please } {<a href="upload.html">}{try again}{</a>} if register [ {<form method="POST" action="echo-login.r" enctype="multipart/form-data"> <i>Forgot your login or need to register ? <br> Please enter your email address here: </i> <input type="text" name="email_address" value=""/> <input type="submit" value="send login by email"/> </form>} ] ] ] Finally, I agree with Carl R. that 'all is a great way to check that conditions are correct to continue. For example: a: make object! [b: 1] either all [ not error? try [a/b] not error? try [a/c] ] [print 'yep][print 'nope] a: make object! [b: 1 c: 2] either all [ not error? try [a/b] not error? try [a/c] ] [print 'yep][print 'nope] where the various fields of cgi-object could be checked in various ways (including existence in this example). HTH --Scott Jones -- To unsubscribe from this list, please send an email to [EMAIL PROTECTED] with "unsubscribe" in the subject, without the quotes.
