Guys what are the best Online resources for learning Compiler Design ?  Would Perl be a viable language to write a Compiler ?
Preferred languages: C/C++, Java, and Ruby.  I am looking for some helpful books/tutorials on how to write your own compiler simply for educational purposes. I am most familiar with C/C++, Java, and Ruby, so I prefer resources that involve one of those three, but any good resource is acceptable.
Logical volume is not mounted but is in use. Please close all applications using this device (eg iscsi) "Images with street signs" CAPTCHA impossible to solve What happens to spirits/souls of other creatues than Elves and Men after their death? Energy-Momentum Tensor in QFT vs. GR Value of momentum of a particle in 1D box prepared in a particular state? What is the value of momentum of particle in 1D box in state $\sin(10\pi x/a)$? My understanding Standing waves representing particle in 1D box is not an momentum eigenstate so if we measure the momentum of particle in this state we may get any value of momentum which gives a distribution whose expectation value tends to zero. Answer key In the answer key it's given that the value of momentum is 5h/a and -5h/a.If we measure the momentum for this state we may get any of these two values.But is this a wrong reasoning because if these was the case,these should mean that 5h/a and -5h/a are the eigenvalue of the following wavefunction which is clearly not. What is the correct answer? Motivation behind standard deviation? Let's take the numbers 0-10.  Their mean is 5, and the individual deviations from 5 are -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5 And so the average (magnitude of) deviation from the mean is $30/11 \approx 2.72$.  However, this is not the standard deviation.  The standard deviation is $\sqrt{10} \approx 3.16$.  The first mean-deviation is a simpler and by far more intuitive definition of the "standard-deviation", so I'm sure it's the first definition statisticians worked with.  However, for some reason they decided to adopt the second definition instead.  What is the reasoning behind that decision? Non-Metrizable Topological Spaces How to show  that $\mathbb{Z}[i]/I$ is a finite field whenever $I$ is a prime ideal? Is it possible to find the cardinality of $\mathbb{Z}[i]/I$ as well?  I know how to show that it is an integral domain, because that follows very quickly. How to add element by element of two STL vectors? Why would using higher ISO and faster shutter speed yield more noise than using lower ISO and slower shutter speed? How does Cypher exit/enter the Matrix without an operator? $$Rad(I)=\{a \in R | \exists n \in \mathbb{N} \text{ such that } a^n \in I\}$$   R is a commutative ring, I is an ideal.   To show that $Rad(I)$ is an ideal of $I$, we have to show that for $a,b \in Rad(I)$ it stands that $a-b \in Rad(I)$ and for $r\in R$ it stands that $a\cdot r\in Rad(I)$, right??   When $a,b \in Rad(I)$ we have that $a,b \in R$ and $a^n, b^m \in I$.   $a-b \in R$.   But how can we show that $(a-b)^x \in I, x \in \mathbb{N}$ ?? Find $P(12)$ when $P(x)={1\over(x+1)}$, for $x=0,1,2,......11$ let $P(x)$ be a polynomial of degree $11$ such that  $P(x)={1\over(x+1)}$, for $x=0,1,2,......11$  then find value of $P(12)$ While writing a proposal at work today I needed to mention a list of things and within that list were multi-part items. It seems like replacing the comma with a semi-colon in this situation would make the sentence easier to understand, but is it correct usage?  With standard punctuation this could get confusing:       Some of my favorite things to do are   camping, playing football and   baseball, watching Laurel and Hardy   Movies, and traveling.   Proposed alternative. Is this acceptable usage?       Some of my favorite things to do are   camping; playing football and   baseball; watching Laurel and Hardy   Movies; and traveling. Is my Ubuntu vulnerable to SambaCry? I read these two threads:         And I got a little bit worried, is my Ubuntu machine safe? Or am I vulnerable to this vulnerability?  The second article mentioned that:     The flaw actually resided in the way Samba handled shared libraries.   The other thing that they say is all versions from versions 3.5.0 onwards since 2010 are vulnerable.     At that time, nearly 485,000 Samba-enabled computers were found to be exposed on the Internet, and researchers predicted that the SambaCry-based attacks also have potential to spread just like WannaCry ransomware widely.   .   I don't have a samba server however I've got samba-libs package installed.  What, if anything, should I do?  I'm running Ubuntu 16.04. dd writing on USB flash drive causes massive reads Find the infinite sum of the series $\sum_{n=1}^\infty \frac{1}{n^2 +1}$ Can my spouse receive an emergency UK visa to visit a funeral? I'm a British national. My grandmother just passed. My wife is Chinese. In general it's a major pain to get my wife a visa to visit the UK, we have never been before.  Is there any way to get an emergency visa to attend the funeral?  What sort of documents would we need? Is there a way to search the latest version of every file in TFS for a specific string or regex? This is probably the only thing I miss from Visual Source Safe...    Currently I perform a Get Latest on the entire codebase and use Windows Search, but this gets quite painful with over 1GB of code in 75,000 files.    EDIT: Tried the powertools mentioned, but the "Wildcard Search" option appears to only search filenames and not contents.  UPDATE: We have implemented a customised search option in an existing MOSS (Search Server) installation. How can I delete everything from my MacBook Pro before selling it? I have a Mac that runs Snow Leopard and I intend to upgrade it to Mountain Lion and sell it on ebay. However, I only have one hard-drive, and I'm sure I can't use something in my OS to delete my OS and all user data.  Is there something for this that's built into the firmware that I can do on boot, or otherwise?   I have source code on my Mac for multiple corporations' proprietary software and I can't risk somebody gaining access through the use of any sort of disk recovery tool. I plan to use a 7 pass erase rather than simply deleting the directory.