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[cl-stm-devel] Is Israel a Democracy? -- The problem with intellectually insecure whites -- Should Christians Support Israeli Terrorism in Gaza?
by Lawrence Auster 23 Jan '09

23 Jan '09

The Jewish State of Israel has no constitution, nor does it name its borders. Israel's hidden constitution is Judaism. Israel's undeclared borders range from the Nile to the Euphrates rivers. Israel's desired jurisdiction extends over the entire Earth. It could not be more clear that the Jewish State follows a foreign policy which obeys Jewish Law as iterated in the Hebrew Bible, the Talmud, Maimonedes, the Cabalah, and the many commentaries and refinements of same. The Jews are genociding the native inhabitants of Palestine, just as their religion advises, and because their religion teaches them to do so. They treat non-Jews as if non-humans, just as their religion requires them to do. They make perpetual war on every nation on Earth, just as their genocidal Jewish God has instructed. The Jews of Israel are simply being Jews. Jews are an existential threat to the human race. Israel contains one third of the Jews of the World. It is not some aberration of the Jewish spirit, but the condensation and concentration of the perverse Jewish mentality, which malady also pervades the remaining two thirds of Jewry, who almost unanimously support the Jewish State, and who certainly do unanimously support the Jewish People and its consistent and constant crimes against the human race. Israel is Jewry and the danger of Israel is the danger of the Jewish People to all others, as the Jews have demonstrated each and every day of their existence. The Jews, the entire Jewish People of 15 million, will not relent until they have wiped out all non-Jews in "Greater Israel". They will not stop destroying all other cultures, nations, religions, ethnicities, races, competition, etc. until they are either stopped, or succeed in their ancient quest to destroy the human race. What Israel is doing is not some reaction to outside forces, nor was the formation of Israel a response to the Holocaust. Israel is simply following the plan laid out in the Jews' religious texts. The Jews have openly planned to take Palestine and genocide the native population of Palestine for some 2,500 years before the Holocaust. The Jews have openly complained that "anti-Semitism" is a threat that gives them the right to genocide the Palestinians, not merely since the advent of Nazism, but for some 2,500 years. The Jewish religion is the Constitution of the Jewish State of Israel, and, to a greater or lesser extent, the constitution of the nature of every Jew alive. The borders of Israel are the range the Jew roams over the entire World. The perverse Jewish mentality is inbred by a Jew's exposure to his parents and to his community. Judaism passes in the spit and slobber of Jewish mother telling her Jewish child that he is a "Jew", as much as Judaism passes in the poison and pain of a Talmudic tractate. The secular Jews did not suddenly come to life after the Enlightenment and the Jewish Reformation a body of vampires that appeared ex nihilo, in vacuo, mostly atheistical and undetached from formally practiced Judaism. Judaism is the Jew. It is a mindset that transcends and supercedes religion. It is a belief set, a way of life, a perception of one's self and one's relation to the World that makes a Jew, a Jew, and a danger to all of humanity. In fact, the religious shell of Judaism is like the stretched and infected skin of a lycanthropic pustule. When you lance it to cure the infection, the virus only becomes more contagious and spills directly on the non-Jew. The secular Jew is a deliberate product of the hyper-religious Jew, a monster created out of the hewed corpses of the fanatically religious Jew, a Golem which is conjured up to enter the World of the non-Jew and poison its blood, and boil its brain with a rabid lunacy that bites and spreads, until the infected community feeds on itself and fills the fields with rotting bloating bodies, where once human beings tilled the soil and tended to their families. The religious Jew created the secular Jew as an army of Esthers who seduce with open thighs, broad smiles, and a Siren call that lures in the non-Jew to cast his skull upon the jagged rocks and color the seas with his blood, sickened and blinded by the venereal disease of Judaism in secular form. Israel is not a secular democracy. It is a religious mockery. It is a rabid bat flying to the ends of the Earth, to end the Earth. No one will be free nor safe until the disease is quarantined and dies out. Source: http://www.ziopedia.org/articles/israel/how_can_israel_claim_to_be_a_%27dem… -------------------- The problem with intellectually insecure whites By Kevin MacDonald January 19, 2009 America will soon have a white minority. This is a much desired state of affairs for the hostile elites who hold political power and shape public opinion. But it certainly creates some management issues � at least in the long run. After all, it�s difficult to come up with an historical example of a nation with a solid ethnic majority (90% white in 1950) that has voluntarily decided to cede political and cultural power. Such transformations are typically accomplished by military invasions, great battles, and untold suffering. And it�s not as if everyone is doing it. Only Western nations view their own demographic and cultural eclipse as a moral imperative. Indeed, as I have noted previously, it is striking that racial nationalism has triumphed in Israel at the same time that the Jewish intellectual and political movements and the organized Jewish community have been the most active and effective force for a non-white America. Indeed, a poll in 2008 found that Avigdor Lieberman was the second most popular politician in Israel. Lieberman has advocated expulsion of Arabs from Israel and has declared himself a follower of Vladimir Jabotinsky, the leading pioneer of racial Zionism. The most popular politician in the poll was Benjamin Netanyahu � another admirer of Jabotinsky. Prime Minister Ehud Olmert and Foreign Minister Tzipi Livni are also Jabotinskyists. The racial Zionists are now carrying out yet another orgy of mass murder after a starvation-inducing blockade and the usual triggering assault designed to provoke Palestinian retaliation � which then becomes the cover for claims that Israel is merely defending itself against terrorism. This monstrosity was approved by overwhelming majorities of both Houses of Congress. The craven Bush administration did its part by abstaining from a UN resolution designed by the US Secretary of State as a result of a personal appeal by the Israeli Prime Minister. This is yet another accomplishment of the Israel Lobby, but one they would rather not have discussed in public. People might get the impression that the Lobby really does dictate US foreign policy in the Mideast. Obviously, such thoughts are only entertained by anti-Semites. But I digress. In managing the eclipse of white America, one strategy of the mainstream media is to simply ignore the issue. Christopher Donovan (�For the media, the less whites think about their coming minority status, the better�) has noted that the media, and in particular, the New York Times, are quite uninterested in doing stories that discuss what white people think about this state of affairs. It�s not surprising that the New York Times � the Jewish-owned flagship of anti-white, pro-multicultural media � ignores the issue. The issue is also missing from so-called conservative media even though one would think that conservatives would find the eclipse of white America to be an important issue. Certainly, their audiences would find it interesting. Now we have an article �The End of White America� written by Hua Hsu, an Assistant Professor of English at Vassar College. The article is a rather depressing display of what passes for intellectual discourse on the most important question confronting white people in America. Hsu begins by quoting a passage in F. Scott Fitzgerald�s The Great Gatsby in which a character, Tom Buchanan, states: �Have you read The Rise of the Colored Empires by this man Goddard?� � Well, it�s a fine book, and everybody ought to read it. The idea is if we don�t look out the white race will be�will be utterly submerged. It�s all scientific stuff; it�s been proved.� Buchanan�s comment is a thinly veiled reference to Lothrop Stoddard�s The Rising Tide of Color which Hsu describes as �rationalized hatred� presented in a scholarly, gentlemanly, and scientific tone. (This wording that will certainly help him when he comes up for tenure.) As Hsu notes, Stoddard had a doctorate from Harvard and was a member of many academic associations. His book was published by a major publisher. It was therefore �precisely the kind of book that a 1920s man of Buchanan�s profile � wealthy, Ivy League�educated, at once pretentious and intellectually insecure � might have been expected to bring up in casual conversation.� Let�s ponder that a bit. The simple reality is that in the year 2009 an Ivy League-educated person, "at once pretentious and intellectually insecure," would just as glibly assert the same sort of nonsense as Hsu. To wit: The coming white minority does not mean that the racial hierarchy of American culture will suddenly become inverted, as in 1995�s White Man�s Burden, an awful thought experiment of a film, starring John Travolta, that envisions an upside-down world in which whites are subjugated to their high-class black oppressors. There will be dislocations and resentments along the way, but the demographic shifts of the next 40 years are likely to reduce the power of racial hierarchies over everyone�s lives, producing a culture that�s more likely than any before to treat its inhabitants as individuals, rather than members of a caste or identity group. The fact is that no one can say for certain what multicultural America without a white majority will be like. There is no scientific or historical basis for claims like �the demographic shifts of the next 40 years are likely to reduce the power of racial hierarchies over everyone�s lives, producing a culture that�s more likely than any before to treat its inhabitants as individuals, rather than members of a caste or identity group.� Indeed, there is no evidence at all that we are proceeding to a color blind future. The election results continue to show that white people are coalescing in the Republican Party, while the Democrats are increasingly the party of a non-white soon-to-be majority. Is it so hard to believe that when this coalition achieves a majority that it will further compromise the interests of whites far beyond contemporary concerns such as immigration policy and affirmative action? Hsu anticipates a colorblind world, but affirmative action means that blacks and other minorities are certainly not treated as individuals. And it means that whites � especially white males � are losing out on opportunities they would have had without these policies and without the massive non-white immigration of the last few decades. Given the intractability of changing intelligence and other traits required for success in the contemporary economy, it is unlikely that 40 more years of affirmative action will attain the outcomes desired by the minority lobbies. Indeed, in Obama's America, blacks are rioting in Oakland over perceived racial injustices, and from 2002 �2007, black juvenile homicide victims increased 31%, while black juvenile homicide perpetrators increased 43%. Hence, the reasonable outlook is for a continuing need for affirmative action and for racial activism in these groups, even after whites become a minority. Whites will also lose out because of large-scale importation of relatively talented immigrants from East Asia. Indeed, as I noted over a decade ago, "The United States is well on the road to being dominated by an Asian technocratic elite and a Jewish business, professional, and media elite." Hsu shows that there already is considerable anxiety among whites about the future. An advertizing executive says, �I think white people feel like they�re under siege right now � like it�s not okay to be white right now, especially if you�re a white male. ... People are stressed out about it. �We used to be in control! We�re losing control�� Another says, "There�s a lot of fear and a lot of resentment." It's hard to see why these feelings won't increase in the future. A huge problem for white people is lack of intellectual and cultural confidence. Hsu quotes Christian (Stuff White People Like) Lander saying, "I get it: as a straight white male, I�m the worst thing on Earth." A professor comments that for his students "to be white is to be culturally broke. The classic thing white students say when you ask them to talk about who they are is, �I don�t have a culture.� They might be privileged, they might be loaded socioeconomically, but they feel bankrupt when it comes to culture � They feel disadvantaged, and they feel marginalized." This lack of cultural confidence is no accident. For nearly 100 years whites have been subjected to a culture of critique emanating from the most prestigious academic and media institutions. And, as Hsu points out, the most vibrant and influential aspect of American popular culture is hip-hop�a product of the African American urban culture. The only significant group of white people with any cultural confidence centers itself around country music, NASCAR, and the small town values of traditional white America. For this group of whites � and only this group � there is "a racial pride that dares not speak its name, and that defines itself through cultural cues instead�a suspicion of intellectual elites and city dwellers, a preference for folksiness and plainness of speech (whether real or feigned), and the association of a working-class white minority with 'the real America.'� This is what I term implicit whiteness � implicit because explicit assertions of white identity have been banned by the anti-white elites that dominate our politics and culture. It is a culture that, as Hsu notes, "cannot speak its name." But that implies that the submerged white identity of the white working class and the lack of cultural confidence exhibited by the rest of white America are imposed from outside. Although there may well be characteristics of whites that facilitate this process, this suppression of white identity and interests is certainly not the natural outcome of modernization or any other force internal to whites as a people. In my opinion, it is the result of the successful erection of a culture of critique in the West dominated by Jewish intellectual and political movements. The result is that educated, intellectually insecure white people these days are far more likely to believe in the utopian future described by Hsu than in hard and cautious thinking about what the future might have in store for them. It's worth dwelling a bit on the intellectual insecurity of the whites who mindlessly utter the mantras of multiculturalism that they have soaked up from the school system and from the media. Most people do not have much confidence in their intellectual ability and look to elite opinion to shape their beliefs. As I noted elsewhere, A critical component of the success of the culture of critique is that it achieved control of the most prestigious and influential institutions of the West, and it became a consensus among the elites, Jewish and non-Jewish alike. Once this happened, it is not surprising that this culture became widely accepted among people of very different levels of education and among people of different social classes. Most people are quite insecure about their intellectual ability. But they know that the professors at Harvard, and the editorial page of the New York Times and the Washington Post, and even conservative commentators like Rush Limbaugh and Sean Hannity are all on page when it comes to racial and ethnic issues. This is a formidable array, to the point that you almost have to be a crank to dissent from this consensus. I think one of the greatest triumphs of the left has been to get people to believe that people who assert white identity and interests or who make unflattering portrayals of organized Jewish movements are morally degenerate, stupid, and perhaps psychiatrically disturbed. Obviously, all of these adjectives designate low status. The reality is that the multicultural emperor has no clothes and, because of its support for racial Zionism and the racialism of ethnic minorities in America, it is massively hypocritical to boot. The New York Times, the academic left, and the faux conservatives that dominate elite discourse on race and ethnicity are intellectually bankrupt and can only remain in power by ruthlessly suppressing or ignoring the scientific findings. This is particularly a problem for college-educated whites. Like Fitzgerald's Tom Buchanan, such people have a strong need to feel that their ideas are respectable and part of the mainstream. But the respectable mainstream gives them absolutely nothing with which to validate themselves except perhaps the idea that the world will be a better place when people like them no longer have power. Hsu quotes the pathetic Christian Lander: "�Like, I�m aware of all the horrible crimes that my demographic has done in the world. ... And there�s a bunch of white people who are desperate � desperate � to say, �You know what? My skin�s white, but I�m not one of the white people who�s destroying the world.�� As a zombie leftist during the 1960s and 1970s, I know what that feeling of desperation is like � what it's like to be a self-hating white. We must get to the point where college-educated whites proudly and confidently say they are white and that they do not want to become a minority in America. This reminds me of the recent docudrama Milk, which depicts the life of gay activist Harvey Milk. Milk is sure be nominated for an Oscar as Best Picture because it lovingly illustrates a triumph of the cultural left. But is has an important message that should resonate with the millions of whites who have been deprived of their confidence and their culture: Be explicit. Just as Harvey Milk advocated being openly gay even in the face of dire consequences, whites need to tell their family and their friends that they have an identity as a white person and believe that whites have legitimate interests as white people. They must accept the consequences when they are harassed, fired from their jobs, or put in prison for such beliefs. They must run for political office as openly pro-white. Milk shows that homosexuals were fired from their jobs and arrested for congregating in public. Now it's the Southern Poverty Law Center and the rest of the leftist intellectual and political establishment that harasses and attempts to get people fired. But it's the same situation with the roles reversed. No revolution was ever accomplished without some martyrs. The revolution that restores the legitimacy of white identity and the legitimacy of white interests will be no exception. But it is a revolution that is absolutely necessary. The white majority is foolish indeed to entrust its future to a utopian hope that racial and ethnic identifications will disappear and that they won�t continue to influence public policy in ways that compromise the interests of whites. It does not take an overactive imagination to see that coalitions of minority groups could compromise the interests of formerly dominant whites. We already see numerous examples in which coalitions of minority groups attempt to influence public policy, including immigration policy, against the interests of the whites. Placing ourselves in a position of vulnerability would be extremely risky, given the deep sense of historical grievance fostered by many ethnic activists and organized ethnic lobbies. This is especially the case with Jews. Jewish organisations have been unanimous in condemning Western societies, Western traditions, and Christianity, for past crimes against Jews. Similar sentiments are typical of a great many African Americans and Latinos, and especially among the ethnic activists from these groups. The �God damn America� sermon by President Obama's pastor comes to mind as a recent notorious example. The precedent of the early decades of the Soviet Union should give pause to anyone who believes that surrendering ethnic hegemony does not carry risks. The Bolshevik revolution had a pronounced ethnic angle: To a very great extent, Jews and other non-Russians ruled over the Russian people, with disastrous consequences for the Russians and other ethnic groups that were not able to become part of the power structure. Jews formed a hostile elite within this power structure � as they will in the future white-minority America; Jews were �Stalin�s willing executioners.� Two passages from my review of Yuri Slezkine's The Jewish Century seem particularly appropriate here. The first passage reminds me of the many American Jews who adopt a veneer of support for leftist versions of social justice and racial tolerance while nevertheless managing to support racial Zionism and the mass murder, torture, and incarceration of the Palestinian people in one of the largest prison systems the world has ever seen. Such people may be very different when they become a hostile elite in a white-minority America. Many of the commentators on Jewish Bolsheviks noted the �transformation� of Jews [after the Bolshevik Revolution]. In the words of [a] Jewish commentator, G. A. Landau, �cruelty, sadism, and violence had seemed alien to a nation so far removed from physical activity.� And another Jewish commentator, Ia. A. Bromberg, noted that: the formerly oppressed lover of liberty had turned into a tyrant of �unheard-of-despotic arbitrariness��. The convinced and unconditional opponent of the death penalty not just for political crimes but for the most heinous offenses, who could not, as it were, watch a chicken being killed, has been transformed outwardly into a leather-clad person with a revolver and, in fact, lost all human likeness. ... After the Revolution, ... there was active suppression of any remnants of the older order and their descendants. ... The mass murder of peasants and nationalists was combined with the systematic exclusion of the previously existing non-Jewish middle class. The wife of a Leningrad University professor noted, �in all the institutions, only workers and Israelites are admitted; the life of the intelligentsia is very hard� (p. 243). Even at the end of the 1930s, prior to the Russification that accompanied World War II, �the Russian Federation�was still doing penance for its imperial past while also serving as an example of an ethnicity-free society� (p. 276). While all other nationalities, including Jews, were allowed and encouraged to keep their ethnic identities, the revolution remained an anti-majoritarian movement. The difference from the Soviet Union may well be that in white-minority America it will not be workers and Israelites who are favored, but non-whites and Israelites. Whites may dream that they are entering the post-racial utopia imagined by their erstwhile intellectual superiors. But it is quite possible that they are entering into a racial dystopia of unimaginable cruelty in which whites will be systematically excluded in favor of the new elites recruited from the soon-to-be majority. It's happened before. Kevin MacDonald is a professor of psychology at California State University�Long Beach. Permanent URL with hyperlinks: http://www.theoccidentalobserver.net/articles/MacDonald-Hsu.html ----------- Should Christians Support Israeli Terrorism in Gaza? A timely discussion between Rev. Ted Pike and Dr. David Duke, one especially important for the Christians in our audience http://www.davidduke.com/mp3/dukeradio090122DukeandPikeonGaza.mp3 In this vital discussion, Rev. Pike and Dr. Duke explore the Pro-Israel attitude of some Christian evangelical organizations, and why their position not only goes directly against Christian morality and decency, but actually is directly opposite of that expressed by Christian Scriptures. Today, Many Christians are instructed that Jews and today�s Israel has a special covenant� with God. In fact, the New Testament in the clearest of language states that the Jews �continued not in my covenant, and I considered them not, saith the Lord.� Here�s the quote that Christians aren�t supposed to notice.: 8:10 Not according to the covenant that I made with their fathers, in the day when I took them by the hand out of the land of Egypt; because they continued not in my covenant, and I regarded them not, saith the Lord. (Hebrews 8:10) They also don�t seem to notice that a 2000 year old Judaic war against Christianity that has been waged since time of Jesus Christ and still goes on today with the most powerful Jewish organizations attempting to destroy European and American traditions, that has even become a war on our Christmas traditions. Dr. Duke and Ted Pike also speak about how over a hundred thousand Christian Palestinians have suffered with their families from anti-Christian Israel! Christian support of Israel has resulted in the very birthplace of Jesus Christ, go from 90 percent Palestinian Christians to 35 percent today because of Israeli terror and occupation. They ask, �How could any Christian in good conscience support the anti-Christian state of Israel, bombing the homes, killing and maiming, torturing and oppressing fellow Christian men, women and children?� This is a vital show for every Christian reader and listener of DavidDuke.com. Next time, you hear someone say, �God tells us that we must support Israel� you will have the clear Christian answer that just the opposite is true! For documentation on this be sure to read some of the well-footnoted, sample chapters of Jewish Supremacism and My Awakening. Source : http://www.davidduke.com/general/should-christians-support-israeli-terroris… ------------------------------------- You or someone using your email adress is currently subscribed to the Lawrence Auster Newletter. If you wish to unsubscribe from our mailing list, please let us know by calling to 1 212 865 1284 Thanks, Lawrence Auster, 238 W 101 St Apt. 3B New York, NY 10025 Contact: lawrence.auster(a)att.net -------------------------------------

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[cl-stm-devel] Higher order transactions
by Hoan Ton-That 19 Aug '06

19 Aug '06

Its now possible to write transactions that take transactions as parameters. Here are two short examples. The first one is `nob' which takes a transaction and turns it into a non-blocking one. It returns T on success or NIL on failure. (deftransaction nob ((tx transaction)) (try (progn tx t) nil)) And with it we can define lots and lots of new operators, like `try-put'. (deftransaction try-put ((cell cell) value) (nob (put cell value))) STM> (defvar *cell* (new 'cell)) *CELL* STM> (perform (try-put *cell* 'hello) :wait? t) T STM> (perform (try-put *cell* 'hello) :wait? t) NIL In the source code, there is a better version of `nob' which returns T and the values of the transaction. The next example is `repeat' which executes a transaction n times. (deftransaction repeat ((tx transaction) n) (if (= n 1) tx (progn tx (repeat tx (- n 1))))) STM> (defvar *counter* (new 'counter :count 1)) *COUNTER* STM> (perform (repeat (increment *counter* 3) 3) :wait? t) 10 Pretty cool huh? Hoan

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[cl-stm-devel] Try-put
by Hoan Ton-That 12 Aug '06

12 Aug '06

I've just made the code walker keep track of the types of transactions. So `try-put' which puts a value in a cell without blocking can be defined as: (deftransaction try-put ((cell cell) val) (try (progn (put cell val) t) nil)) And the macroexpansion is: (PROGN (EVAL-ALWAYS (PUSHNEW '(TRY-PUT NIL NIL) *TRANS-FUNS*)) (DEFMETHOD TRY-PUT ((CELL CELL) VAL) (ORELSE (TRANS (PROGN (UNTRANS (PUT CELL VAL)) T)) (TRANS NIL))) 'TRY-PUT) So the code walker now knows that `orelse' takes two transactions as arguments. If you looked at the `pushnew' you would see some extra stuff. We're pushing '(try-put nil nil) instead of 'try-put. The two NILs means that `try-put' takes two arguments, both which aren't transactions. Hey, have a look at the type of `orelse': STM> (assoc 'orelse *trans-funs*) (ORELSE T T) `orelse' takes two transactions as its arguments. Thats why its arguments are left inside a `trans'. Neat huh? This suggests a higher order operator called `nob' which turns any blocking action into a non-blocking one which returns t on success or nil on failure: (deftransaction nob ((tx transaction)) (try (progn (funcall tx) t) nil)) However currently the macroexpansion doesn't work. The (funcall tx) form isn't untransed. I'm going to fix this up (the handling of funcall and apply), and extract the types from declarations. Then we'll call it a summer. Hoan

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[cl-stm-devel] Cell example
by Hoan Ton-That 01 Aug '06

01 Aug '06

Hey everyone, Substantial progress has been made since I last mailed. We no longer need special macros like `progt', `progt1' and `tif'. There is a code walker which lifts LISP forms into the STM monad. I'll guide you through the example of a concurrent mutable cell, and its expansions. A cell is a mutable location that is either empty or full with a value. Its the same as an MVar in Haskell. [1] First off here is the class definition. We have to distinguish between empty and full, hence the gensym. (defparameter *empty-cell* (gensym "EMPTY")) (deftclass cell () ((value :accessor value-of :initarg :value :initform *empty-cell*))) Now here is the interface to tell if the cell is empty: (deftransaction empty? ((cell cell)) (eq (value-of cell) *empty-cell*)) The macro expansion for this transaction is: (PROGN (EVAL-ALWAYS (PUSHNEW 'EMPTY? *TRANS-FUNS*)) (DEFMETHOD EMPTY? ((CELL CELL)) (TRANS (EQ (VALUE-OF CELL) *EMPTY-CELL*))) 'EMPTY?) Notice that the `eq' is wrapped around with a `trans'. So `empty?' returns a transaction, that when executed returns whether or not the cell is empty. Likewise the transaction `empty!' makes the cell empty. (deftransaction empty! ((cell cell)) (setf (value-of cell) *empty-cell*)) Its macroexpansion is similar to `empty?'s: (PROGN (EVAL-ALWAYS (PUSHNEW 'EMPTY! *TRANS-FUNS*)) (DEFMETHOD EMPTY! ((CELL CELL)) (TRANS (LET ((#:G907 CELL)) (FUNCALL #'(SETF VALUE-OF) *EMPTY-CELL* #:G907)))) 'EMPTY!) The `setf' is expanded by the code walker. Now lets move onto some more complex transactions. `take' blocks when the cell is empty, waiting for it to be filled. When the cell is filled, `take' returns the value in the cell, and then empties it. (deftransaction take ((cell cell)) (if (empty? cell) (retry) (prog1 (value-of cell) (empty! cell)))) The above code reflects the intent of `take' very well. The macroexpansion is: (PROGN (EVAL-ALWAYS (PUSHNEW 'TAKE *TRANS-FUNS*)) (DEFMETHOD TAKE ((CELL CELL)) (TRANS (IF (UNTRANS (EMPTY? CELL)) (UNTRANS (RETRY)) (LET ((#:G908 (VALUE-OF CELL))) (UNTRANS (EMPTY! CELL)) #:G908)))) 'TAKE) Like before, the body of the `defmethod' is wrapped up in a `trans'. But if you look closely, you can see a few `untrans' forms. Why are they necessary? Remember the `empty?', `retry' and `empty!' return transactions, not values. So we have to execute them to get a result. If there were no `untrans' forms, the `if' would always be non-nil and the transaction would return a transaction that retries. Quite useless. The code-walker keeps track of which LISP forms return transactions. In the macroexpansion of `deftransaction' there is a `pushnew' which adds it to the list of transactions. `put' blocks when the cell is full, waiting for it to become empty. When its empty, it writes a value in. (deftransaction put ((cell cell) val) (if (not (empty? cell)) (retry) (setf (value-of cell) val))) The corresponding macroexpansion is: (PROGN (EVAL-ALWAYS (PUSHNEW 'PUT *TRANS-FUNS*)) (DEFMETHOD PUT ((CELL CELL) VAL) (TRANS (IF (NOT (UNTRANS (EMPTY? CELL))) (UNTRANS (RETRY)) (LET ((#:G904 CELL)) (FUNCALL #'(SETF VALUE-OF) VAL #:G904))))) 'PUT) There is still more to be done on the code walker though. It doesn't work correctly for transactions that take transactions as arguments. So that means it won't walk `orelse' correctly. Here is a non-blocking version of `put'. If `try-put' can't put `val' in `cell' immediately, it returns nil and exits. If the value was put without failure, it returns t. (deftransaction try-put ((cell cell) val) (try (progn (put cell val) t) nil)) The macroexpansion for this is currently: (PROGN (EVAL-ALWAYS (PUSHNEW 'TRY-PUT *TRANS-FUNS*)) (DEFMETHOD TRY-PUT ((CELL CELL) VAL) (ORELSE (PROGN (UNTRANS (PUT CELL VAL)) T) NIL)) 'TRY-PUT) The arguments to `orelse' should be wrapped in a `trans'. So the correct expansion would look like this: (defmethod try-put ((cell cell) val) (orelse (trans (progn (untrans (put cell val)) t)) (trans nil))) This involves finding out the types of the arguments that transactions take at compile time. My plan is to have it extracted from the `deftransaction' definitions. There are also working examples of a concurrent queue (the equivalent of Java's ArrayBlockingQueue[2]), and multicast channels. [1] Hoan [1] Composable Memory Transactions (http://research.microsoft.com/~simonpj/papers/stm/stm.pdf) [2] Lock Free Data Structures using STM in Haskell (http://research.microsoft.com/~tharris/papers/2006-flops.pdf)

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[cl-stm-devel] What next for CL-STM?
by Hoan Ton-That 15 Jul '06

15 Jul '06

Hello everyone! I'm wondering what we should work on next for CL-STM. I haven't worked on it for a few days. What would you like to see done with CL-STM? Has anyone here got it working? I'd be happy if you have, and if you haven't I can help out if you would like. I'm currently working on the code walker, and I think I'll be done with it by Wednesday. But besides that, I have worked on easy things like documentation. Hoan

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[cl-stm-devel] Documentation
by Hoan Ton-That 05 Jul '06

05 Jul '06

This is a quick note letting you know that there is now an online API reference to CL-STM: http://www.common-lisp.net/project/cl-stm/doc The documentation is generated by qbook, which extracts it from the source code. qbook is childly simple to use. Hoan

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[cl-stm-devel] Retry
by Hoan Ton-That 03 Jul '06

03 Jul '06

Yesterday I gave an example of the operator `try'. Today, you'll see how `retry' nicely complements it. The previous code tried to increment one of two counters. It didn't matter which one we incremented as long as we incremented! Lets generalize from that example to increment any counter in a list of counters: (deftransaction increment-any (counters) (tif (trans (null counters)) (retry) (try (increment (car counters)) (increment-any (cdr counters))))) Here `tif' is a macro just like `if', but it takes transactions as its test and branches. That's why the (null counters) is wrapped up in a `trans'. As you can infer, that means the return value of `retry' and `try' are transactions. Looking at the second clause tells us that this is a standard car/cdr recursion. We try to increment the first counter, and if we fail, we try the rest of them. The base case is where we call retry. So if the list is empty, the transaction is *aborted* and starts from scratch again. The transaction waits on all the variables that have been read until `retry' was called. This guarantees that the transaction will eventually commit. Here is an example: STM> (progn (defvar *c1* (new 'counter)) (defvar *c2* (new 'counter))) *C2* STM> (acquire-lock (lock-of (count-of *c1*))) T STM> (acquire-lock (lock-of (count-of *c2*))) T STM> (perform (increment-any (list *c1* *c2*))) [debugging output elided...] STM> (values (value-of (count-of *c1*)) (value-of (count-of *c2*))) 0 0 STM> (release-lock (lock-of (count-of *c1*))) NIL STM> (unwait (count-of *c1*)) [debugging output elided...] STM> (values (value-of (count-of *c1*)) (value-of (count-of *c2*))) 1 0 So that was just the same as yesterday. But we can do better. `increment-any' is just a special case of trying any transaction down a list, just like `map' is a special case of apply a function down a list. So the equivalent would be: (deftransaction try-list (transaction list) (tif (trans (null list)) (retry) (try (funcall transaction (car list)) (try-list transaction (cdr list))))) And we could now define `increment-any' as: (deftransaction increment-any (counters) (try-list #'increment counters)) Now running it gives us: STM> (perform (increment-any (list *c1* *c2*))) [debugging output elided...] STM> (values (value-of (count-of *c1*)) (value-of (count-of *c2*))) 2 0 And indeed it works the same as before. Indeed we could even use `try-list' in many other situations, like reading from a socket like Unix's select. Now I am in a bit of a conundrum with regards to the interface that CL-STM should have. At the moment I'm not happy with using all these new macros like `progt', `progt1', `tif' and so on because it means the programmer has to learn all these new names that are just variations of the standard CL ones. Its also a pain to figure out where to use `trans' and `untrans'. I've started some work on a code walker that transforms CL forms into STM ones. I have the equivalents of `tlet', `progt' and `tif' implemented. Even better is the code walker handles macro expansion, so that `cond', and `prog1' will be taken care of. BTW, this code walker will only traverse forms inside a `deftransaction'. Ideally we'd like to write code without explicit `trans' and `untrans'. Even in the simple `increment-any' example, we had to use `trans'. It would be nice if we could tell in advance whether or not a particular expression is a transaction or not. But Common Lisp doesn't have a type system. But here is what we know: Forms like `(trans ...)' are transactions. A form is a transaction if its car is a symbol defined with `deftransaction'. So (increment-any ...) is a transaction. Assuming all transactions are take the form above, we can infer that anything else is not a transaction. So (null ...) is not a transaction, and thus the walker can wrap it with `trans'. The above analysis doesn't work for higher-order functions. It assumes incorrectly that (reduce ...) is doesn't return a transaction. But it could return a transaction depending on the function passed to it. So the analysis only work on first-order functions. I'm wondering if this is the best we can do? I've still got more thoughts on this but now I'm asking you. What interface would you like? Do you mind writing `trans' and `untrans'? Would you accept a half-solution? Whatever, just tell me whats on your mind. Did you have a good day? Are you following the world cup? Hoan

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[cl-stm-devel] Try
by Hoan Ton-That 02 Jul '06

02 Jul '06

Here is an example of the `try' operator. From the documentation: "Return a transaction that executes the transactions in BODY atomically until one succeeds. The return value of the transaction is the value of the transaction that succeeds." Here we have two counters *c1* and *c2*. (defvar *c1* (new 'counter)) (defvar *c2* (new 'counter))) STM> (perform (try (increment *c1*) (increment *c2*))) [debugging output elided...] STM> (values (value-of (count-of *c1*)) (value-of (count-of *c2*))) 1 0 Here, the first transaction (increment *c1*) succeeds, and we're done. Thus the values of the counters are 1,0 respectively. This is what happens when we can't increment *c1*. STM> (acquire-lock (lock-of (count-of *c1*))) T STM> (perform (try (increment *c1*) (increment *c2*))) [debugging output elided...] STM> (values (value-of (count-of *c1*)) (value-of (count-of *c2*))) 1 1 Since the first transaction (increment *c1*) failed, the second one (increment *c2*) was run and succeeded. So far the behaviour of `try' is very similar to the `or' operator. Now what happens when we can't increment either counter? STM> (acquire-lock (lock-of (count-of *c2*))) T STM> (perform (try (increment *c1*) (increment *c2*))) [debugging output elided...] STM> (values (value-of (count-of *c1*)) (value-of (count-of *c2*))) 1 1 The values are still the same as before. However the transaction is still waiting for either *c1* or *c2* to be freed. Here is what happens when we free *c2* and notify the threads waiting on it: STM> (release-lock (lock-of (count-of *c2*))) NIL STM> (unwait (count-of *c2*)) [debugging output elided...] STM> (values (value-of (count-of *c1*)) (value-of (count-of *c2*))) 1 2 The whole transaction has been retried from the beginning. The first counter was still locked so the transaction (increment *c1*) failed. The second transaction (increment *c2*), succeeded. Whenever a variable is written to memory (when a log is committed), all threads waiting on that variable are woken up automatically with `unwait'. See the code in the `commit' function for more details. That guarantees that transactions eventually commit. Hoan

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[cl-stm-devel] Binding variables
by Hoan Ton-That 01 Jul '06

01 Jul '06

Hey everyone, Today, I added `tlet' a There is a slight problem with our previous higher-order function: (deftransaction sleep-after (seconds transaction) transaction (trans (sleep seconds))) The return value of the new transaction is not the same as the return value of the input transaction. Instead what `sleep-after' does is always return NIL, because `sleep' returns NIL. What we need is a way to bind the value of `transaction' to a variable. Hence `tlet'. Here is how we could write `sleep-after' correctly: (deftransaction sleep-after (seconds transaction) (tlet ((val transaction)) (trans (sleep seconds)) (trans val))) Now if you looked through the debugging output when typing `(perform (sleep-after 2 (increment *c*)))', with both versions, you will see a line looking like: 20:33 STM-LOGGER/+DRIBBLE+: Transaction finished executing with: 6 or, with the old version: 20:33 STM-LOGGER/+DRIBBLE+: Transaction finished executing with: NIL If you were very observant, you would have noticed that the `tlet' in `sleep-after' could be replaced with a `prog1'-like construct. We can define `progt1' in terms of `tlet': (defmacro progt1 (&body body) (with-unique-names (val) `(tlet ((,val (trans ,(car body)))) ,@(cdr body) (trans ,val)))) And thus `sleep-after' becomes: (deftransaction sleep-after (seconds transaction) (progt1 transaction (trans (sleep seconds)))) which is much nicer. However, we quickly run into a problem. We now have to define a whole slew of transactional equivalents of `prog2', `multiple-value-prog1', and so on. When translating an the MVar example from Haskell to Common Lisp, I even had to write a new version of `if'! The next step is to write a code-walker that converts Common Lisp forms into the transactional equivalent. Hoan

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[cl-stm-devel] Counter example
by Hoan Ton-That 30 Jun '06

30 Jun '06

Hey folks, Transactions can be parametrized by other transactions. For testing purposes we may want a transaction to pause for two seconds after its calculation. We can define a higher order transaction that does this: (deftransaction sleep-after (seconds transaction) transaction (trans (sleep seconds))) With the counter example loaded (the source can be found in src/examples/counter.lisp) we can now see what happens when two transactions conflict. STM> (defvar *counter* (new 'counter)) *COUNTER* STM> (progn (perform (sleep-after 2 (increment *counter*))) (perform (sleep-after 2 (increment *counter*)))) [debugging output elided...] STM> (value-of (count-of *counter*)) 2 STM> If you looked at the debugging output you would see one of the transactions has retried due to an inconsistent log. I'm sorry that I haven't been posting regularly, but I've been making steady progress. I'm managing to work on it, however small everyday. I'll be posting more regularly this week with snippets like these. Hoan

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