whenxpisunpopular.html

极限编程 Extream Programing

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And so I post to the XP pages, trying to understand the stuff. And,
as of 8:17 PM PST <em>(but what day?)</em>, failing to get it. 
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<a href="http://c2.com/cgi/wiki?WilliamGrosso">WilliamGrosso</a>
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Interesting that XP comes across as <a href="http://c2.com/cgi/wiki?NotDoingDesign">NotDoingDesign</a>, when what I read is only that XP is against <a href="BigDesignUpFront.html">BigDesignUpFront</a>. Using <a href="http://c2.com/cgi/wiki?CrcCards">CrcCards</a> sounds like XP is doing design, OK not formally documented in a CASE tool. XP seems to be saying <a href="TheSourceCodeIsTheDesign.html">TheSourceCodeIsTheDesign</a>, which is a really hot button to judge by the size of that page.  --<a href="http://c2.com/cgi/wiki?PeteMcBreen">PeteMcBreen</a> (who updated the first list with #4 through #8)
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I think much of the reaction comes against the rhetoric (perhaps sometimes advanced a little...pushily?) rather than the ideas.  Like <a href="http://c2.com/cgi/wiki?WilliamGrosso">WilliamGrosso</a> and his colleague, I find much of it familiar, and what doesn't match what I practice doesn't for the most part seem wrong to me.  Some of the language that looks on the surface like <a href="http://c2.com/cgi/wiki?NotDoingDesign">NotDoingDesign</a> rubs me the wrong way, but remember that XP says elsewhere that it does <strong>more</strong> design than other approaches, so I don't take that at face value.
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I think the use of reductionist rhetoric gives a certain <a href="http://c2.com/cgi/wiki?StoneSoup">StoneSoup</a> quality to the whole thing.
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--<a href="http://c2.com/cgi/wiki?JimPerry">JimPerry</a>
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Two things that seem to have gotten stepped upon:
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<li> People who have actually experienced XP find it to be the most enjoyable and productive form of software development they have ever used.
<li> If y'all will point out places where we seem to be recommending <a href="http://c2.com/cgi/wiki?NotDoingDesign">NotDoingDesign</a>, I'll check 'em out and fix 'em.  
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Thanks!  --<a href="RonJeffries.html">RonJeffries</a>
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It seems that &quot;design&quot; seems to be the center of a lot of contention about XP.  I have to say, coming from the shrinkwrap software world, that this seems almost surreal to me.  At least in the projects I've been involved in, OMT, UML, and CRC Cards are <em>unheard</em> of.  When design is done up front, it's done on white boards or notebook paper.  Certainly no persistent design data is kept.  These weren't little projects, either.  Does everybody in the Smalltalk world obsess over design?  Just curious.  --<a href="http://c2.com/cgi/wiki?CurtisBartley">CurtisBartley</a>
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Before I ever got into consulting or building business applications, the same was true for me.  I came from the shrinkwrap world (even worked at MS at one point) and I never heard of or had to deal with anything but design meetings, e-mail, and whiteboards.  These things were communication devices that allowed team to collaborate in the design and development of a product.  But these products have different forces that come into play, so that's potentially why emphasis is different and design seems surreal to you.
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For example, at Microsoft a developer on the Word team might be thinking about conquering the world -- just joking ;-) -- the developer might be thinking about design regarding page repagination, whereas a developer building a customer management system might be trying to understand an order processing subsystem and may need to communicate with users and technology folks to better understand the business process and use cases.
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--<a href="http://c2.com/cgi/wiki?PhilipEskelin">PhilipEskelin</a>
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I've noticed in reading many of XP <a href="http://c2.com/cgi/wiki?WikiWikiWeb">WikiWikiWeb</a> pages that they don't seem to emphasize or reference/compare/contrast with existing work.  If this is because XP is so groundbreaking and new that it simply doesn't relate to any existing work, then perhaps people are criticizing it for its methods in order to better understand it and be able to apply it to their own projects.
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--<a href="http://c2.com/cgi/wiki?PhilipEskelin">PhilipEskelin</a>
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<em>I've been assuming all along that the spirited discussions that come around XP are stimulated by people who are trying to understand. It would be better to compare to other methodologies - as for me I'm not sure how to do that. One way would be for a questioner to say: &quot;In Synchrony we do such and such because of thus and so, how does XP address this?&quot;, and we'd try to answer. I think that's what we've been doing anyway, just without the back reference to Synchrony.  --<a href="RonJeffries.html">RonJeffries</a></em>
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Ron,  assuming that you still think that there would be any value in comparing XP with any other method, perhaps tying to fill in the <a href="http://c2.com/cgi/wiki?XpFrame">XpFrame</a> (and the other examples of a <a href="http://c2.com/cgi/wiki?ProblemFrame">ProblemFrame</a>) would help? --<a href="http://c2.com/cgi/wiki?KeithBraithwaite">KeithBraithwaite</a>
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<strong>Ferraris are popular - you just don't see many of them.  --<a href="http://c2.com/cgi/wiki?ChetHendrickson">ChetHendrickson</a></strong>
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<em>Alistair has a very good paper on his web site, see <a href="http://c2.com/cgi/wiki?MethodologySpace">MethodologySpace</a>, and it attempts to build a vocabulary for comparing methodologies.  I also think that he isolates one of the reasons that I like XP so much.  Without giving it away, I'll just say that it has to do with fear.  -- <a href="http://c2.com/cgi/wiki?MichaelFeathers">MichaelFeathers</a></em>
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I like most of XP. And in a situation where I'm building a piece of software unlike any piece of software I've built before, I think it is pretty ideal.
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My problem comes because I think it throws away previous domain-specific experience.  If I'm building my umpteenth payroll system/object-relational mapping/whatever, then I have a lot of real practical knowledge about the way the future is likely to be. And so the trade-off about <a href="YouArentGonnaNeedIt.html">YouArentGonnaNeedIt</a> gets skewed.  Go look at that page now, and see the arguments against implementing a future feature. If I've been to that future before, then this list looks much less frightening to me.--<a href="http://c2.com/cgi/wiki?DaveCleal">DaveCleal</a>
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Ran across the phrase <em>stereotyped conceptualization</em> on another page, and liked it.  Seems applicable.  I currently am working on the third major re-write of a 10 year old system.  We have a lot of knowledge about what the current system turned out to be.  We also have a lot of domain knowledge - we have developers and other folks who have been in it from the beginning, some of whom have reached respected positions in the field and qualify as domain experts.  We have a lot of features and hooks and other garbage in our current system because someone will need this (no-one does).  
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<li>) None of this tells us the stories our customers will present (the market is changing rapidly- old players are doing business in new ways and there are lots of new players with their own ideas).  
<li>) There is an awful lot of junk (that has to be maintained) in the current system because 
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	  a) SOMEONE will need it (no-one yet, but we can still hope, right?) and 
	  b) at some point (not now, of course) there was a technical limitation that led to a particular design.  
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Those folks that have been here a while have to be constantly reminded that these decisions and designs need to be re-evaluated (or just plain made in the first place) in terms of what our customers want today. 
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It's nice to have a lot of domain knowledge and experience - it makes answering some questions easy.  It doesn't mean I know what I'm going to need this time. I might make better guesses, but do I guess right enough to make it pay off?  I've re-written several systems now (systems I was involved in from v0.1), and written the same system more than once.  I don't guess well enough the second (or third) time to make it pay off (YMMV).  If only users would be happy with the same thing with go-faster stripes on, maybe I'd do better... --<a href="http://c2.com/cgi/wiki?BillJamison">BillJamison</a>
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Sure, the hooks you haven't used in ten years should be removed from the new build.  Equally, the hooks you used all the time from years 3-10 should go straight into the new build. For me, this kind of &quot;guess&quot; works the second time.  Maybe the difference implied in your comment is that your market (what it it?) changes so rapidly and fundamentally that your previous experience is invalid. Which means that we aren't considering the same situation.
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(my experiences span process control - physics is quite stable (grin) - systems level software (I'd say pretty stable) - and derivatives trading (and perhaps surprisingly, even there, the basics change at a slower rate than that at which the software gets rewritten)). --<a href="http://c2.com/cgi/wiki?DaveCleal">DaveCleal</a>
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There are different ways to categorize things, but ultimately there are three 
reasons <a href="http://c2.com/cgi/wiki?WhyXpIsUnpopular">WhyXpIsUnpopular</a>:
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1. XP says things that people are not willing to accept.
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2. People believe that XP says things that they are not willing to accept.
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3. That heretic <a href="RonJeffries.html">RonJeffries</a> has the audacity to answer questions that people 
ask him and to defend his beliefs. (Burn him at the stake!)
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When I was a kid, my mom would tell me that I needed a haircut. I would 
protest. She would tell me not to protest because it was no big deal. And I 
would think <em>if it's no big deal, why are bugging me about it so much!</em>
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Ron said <a href="http://c2.com/cgi/wiki?ExtremeProgrammingIsNotTheOneTrueFaith">ExtremeProgrammingIsNotTheOneTrueFaith</a>. I think there are some 
that are not satisfied with that. They want a confession that XP is not a True 
Faith at all. XP says things they are not willing to accept. It <em>can't</em> be a 
True Faith because it contradicts their True Faith!
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Perhaps I am misreading people. I will keep an open mind. I ask that others 
also keep an open mind. --<a href="http://c2.com/cgi/wiki?KielHodges">KielHodges</a> (wondering if he smells something burning :-)
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Open but not uncritical. If there is one strictly rational activity going on in the world today, surely software development is (should ;-) be it. I'm talking about the construction of code artifacts here. And surely being rational means that you don't get to choose what you believe. If the evidence is there, you <em>must</em> accept the claim (modulo the Scientific Method). 
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A little while ago one presenter of a course on Fagan inspections gave two reasons for using that tool: 
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<li>The logic of it is inescapable
<li>The record shows that it works
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Is not too much of the XP debate ignoring both of these, and especially the second? I'm unconvinced on XP either way because I just don't have enough evidence to make a decision. But every time I read a comment along the lines of 
&quot;<strong>if</strong> XP were used 
<strong>then</strong> good things would happen/be possible, I so assert&quot;
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For example:
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<li> &quot;It is <em>entirely possible</em> that a large project using XP methodology would never need to go beyond it.&quot; on <a href="ExtremeProgrammingMayScaleUp.html">ExtremeProgrammingMayScaleUp</a>
<li> &quot;Extreme programming <em>quite possibly</em> works in more than one setting,&quot; on <a href="ExtremeProgramming.html">ExtremeProgramming</a>
<li> &quot;In XP we rely on the engineer to be doing the right thing, and on pair programming and collective code ownership to pick up the slack. It <em>seems</em> to work ... but does it really?&quot; on <a href="http://c2.com/cgi/wiki?ExtremeProgrammingCodeReviews">ExtremeProgrammingCodeReviews</a>
<li> &quot;XP has not been tried in larger groups. <em>We believe</em> that the values will surely apply, and that many of the practices will survive. We have no proof.&quot; on <a href="ExtremeProgrammingInContext.html">ExtremeProgrammingInContext</a>
<li> &quot;I get the impression XP is designed for developing new software...It may be hard...to develop <a href="UnitTests.html">UnitTests</a> for testing modules in isolation, if such modules were never meant to be run in isolation.&quot; response: &quot;I <em>suppose in principle</em> this is possible.&quot;
<li> &quot;<em>Could we do <a href="PairProgramming.html">PairProgramming</a> across the edges, ...? Perhaps we'd have code ownership by team, ...? Could we still do <a href="ContinuousIntegration.html">ContinuousIntegration</a>? How much paperwork could we still not do? </em>&quot; on <a href="LargeExtremeProgramming.html">LargeExtremeProgramming</a>
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