error in position function in Lisp
How do I find the index of an element in a list in Racket?
Execute function when post is published I try to use this function i have created when a post is published for the first time.  function a_new_post($post){   $post_id = $post-&gt;ID;    if ( !get_post_meta( $post_id, 'firstpublish', $single = true ) ) {       // ...run code once       update_post_meta( $post_id, 'firstpublish', true );   } } add_action( 'draft_to_published', 'a_new_post' );   I can't see anything wrong with it, but when i try to create some sample posts i check the database and the field "firstpublished" has not been created.  Does anyone see anything wrong? Is there a problem with Beamer in the latest MiKTeX update? Simple past or past perfect with "by" and years What is the difference between      He became a star by 1990's.     He had become a star by 1990's.    Is the first sentence correct? If yes, then please tell me the difference between the two. How to copy a file to multiple directories using the gnu cp command How does Ethernet know how long a frame is? Some irreducible character separates elements in different conjugacy classes Let $x$ and $y$ be elements that are not conjugate in $G$.  Then there is some irreducible character $\chi$ such that $\chi(x) \not = \chi(y)$.   Clearly the "irreducible" part isn't important, since any character can be written as the sum of irreducible characters, but I'm having trouble going beyond that.  I'd appreciate a good hint over a full answer, and I'd be most interested in a way to construct a group representation $\varphi:G \to GL(V)$ of $G$ such that the character of the representation takes different values on $x$ and $y$. Dodecagon Area Question The distance between two opposite vertices of the dodecagon is 2. Find the area of the dodecagon.  Is there any way to do this without trigonometry?  And could you include a proof also? :O Configure proxy for APT? passive Vs active or omission of 'which is' What is the part of speech of 'regarded' in the following?     "a quality of beauty and intensity of emotion regarded as characteristic of poems"    Why isn't it "... [which is] regarded ..."?  And in another case:      "a small lizard with wide feet, found especially in warm countries"     And also:      "Words used to describe writing or speech style"    In all these examples, why shouldn't the verbs be in their passive form (e.g. which is found, words that are used)?   I am a ESL learner and I am very confused by these usages! What is the Relationship between the Rank and the Number of Eigenvalues? for (a) it says it can't be rank 1 because there is only one non zero eigenvalue? I understand it can't be 0 or 3 but I don't understand how you can conclude we have 2 just by knowing how many eigenvalues we have. Toast message with Chinese characters, is it a virus? I recently received some updates today from the Play Store. Every so often a pop notification, one of those bubble ones at the bottom of the screen with Chinese characters.  The most recent update I've noticed is the ES File Explorer. I wouldn't mind, but my device is rooted and so I am at risk. I have a screenshot of the notification.  My device is the Samsung Galaxy Tab A 9.7 and I have stock ROM installed.    What my question(s) are: Do I have a virus (it's not being picked up by Avast) and if I do, how do I remove it? I am looking at some code and it has this statement:    ~ConnectionManager() {     Dispose(false); }   The class implements the IDisposable interface, but I do not know if that is part of that the tilde(~) is used for. Show that a ring is commutative if it has the property that ab = ca implies b = c when $a\neq 0$ Show that a ring is commutative if it has the property that ab = ca implies b = c when $a\neq 0$.   This is my proof to show that a ring is commutative if it has the property that ab = ca implies b = c.  We need to show that if x, y ∈ R then xy = yx. Let a = x, b = yx and c = xy. Then ab = x(yx) = (xy)x = ca. Thus, by the hypothesis, b = c, or xy = yx. Thus, for x, y ∈ R we have xy = yx.   How would I show when $a\neq 0$? I'm looking for a short story whose title I can't remember.  In it a wealthy man practices cloning and consciousness transfer to achieve immortality, often parading older bodies around his estate naked (not a nice guy). The story follows a final transplant, which doesn't go as expected. The man is left trapped with his memories and no ability to speak, while the clone walks off behaving exactly as he would. Including section titles in fancyhf headers Why is the triangle inequality property important for metric spaces? There is a property in the axiomatization of metric space: $d(x,z)\le d(x,y)+d(y,z)$. I understand that property applies well when it come to the measure of distances among points. However, that property seems to be irrelevant in the definitions of continuity, open set and some other key concepts.  My topology book says that it is asserting "the transitivity of closeness", a vague term that loses me. So why is that property important? Why did the founders (if any) of topology consider it at the first place? And what if that property is missed? TeXnicCenter & Adobe Acrobat 10 I have two user profile fields "Last Name" and "First Name". I also have a user list views. I want to expose "Name" as filter which can search for both Last Name and First Name. How can I do single filter of combination of those two fields? Can I create it from views UI?  One possible way is to create another profile field "Name" which will be hidden in the form. On user save, I would combine the two field values into the "Name" field and then expose it as filter in the views. But this solution is hard coding and it needs to write hooks. A book suggests that we should not interchange "so" and "so that". "So" means "therefore", and "so that" means "in order that". However, it seems to me that in many cases they don't actually have a difference. For example:     Alice got up at 5:00 A.M., so that she could drive her son to school.   If I substitute "so that" with "so", this sentence presents the exact same causal relation to me:     Alice got up at 5:00 A.M., so she could drive her son to school.   I must have missed something here, since English is my second language. Could somebody explain the difference? When and how did "pretty" enter English as an intensifying adverb? Today I saw an idiomatic road sign: "Pretty Muddy". I found this lack of strict English on a road sign unusual (on par with my "Dead Slow" official speed limit sign in Leeds, pic below), but as it turned out it's a charity race and the signs were merely directions.  This got me thinking however, how do words like "pretty" and "dead" as   end up in English? Taking "pretty" as an example, when did this first appear?     I wonder how fast you have to be going before they stop you. How would this hold up in court?