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Advantages of Antlr (versus say, lex/yacc/bison) [closed]
...ojects, usually translators (such as a subset of EDIF streamed into an EDA app). Additionally, I've had to support code based on lex/yacc grammars dating back decades. So I know my way around the tools, though I'm no expert.
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Difference between require, include, require_once and include_once?
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Use
require
when the file is required by your application, e.g. an important message template or a file containing configuration variables without which the app would break.
require_once
when the file contains content that would produce an error on subsequent inclusion, ...
Using git, how do I ignore a file in one branch but have it committed in another branch?
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This solution appears to work only for certain, patched versions of git. See a new answer pointing to workarounds and another answer and subsequent comments for a hint which versions may work.
I wrote a blog post on how to effectively us...
Is storing a delimited list in a database column really that bad?
... list in sorted order.
To solve these problems, you have to write tons of application code, reinventing functionality that the RDBMS already provides much more efficiently.
Comma-separated lists are wrong enough that I made this the first chapter in my book: SQL Antipatterns: Avoiding the Pitfalls ...
Rails: How can I set default values in ActiveRecord?
...please use Base.after_initialize :method instead. (called from /Users/me/myapp/app/models/my_model:15)
Therefore I'd say write an after_initialize callback, which lets you default attributes in addition to letting you set defaults on associations like so:
class Person < ActiveRecord::Base
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How to list the files inside a JAR file?
...files inside this subdirectory? Or I need to unzip this jar file? I highly appreciate your help !
– Ensom Hodder
Aug 11 '12 at 22:39
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How to wait for a keypress in R?
... the console:
cat ("Press [enter] to continue")
line <- readline()
Wrapping into a function:
readkey <- function()
{
cat ("Press [enter] to continue")
line <- readline()
}
This function is the best equivalent of Console.ReadKey() in C#.
Method 2
Pause until you type the [ent...
Why can't a text column have a default value in MySQL?
...r platforms it is often a warning. While not a bug, it's possible to get trapped by this if you write code on a lenient platform, and later run it on a strict platform:
Personally, I do view this as a bug. Searching for "BLOB/TEXT column can't have a default value" returns about 2,940 results on ...
Android Studio needs JDK 7 for Android-L mac
I was trying to look how my app looks in material design and I would like to use the new cards lib.
My Problem is, that it's giving me this error within my gradle file and I need to fix that.
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How to display hidden characters by default (ZERO WIDTH SPACE ie. ​)
...idn't show them, which was causing problems with parsing config file of my app... I discovered it accidentally in vi.
2 Ans...