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Getting parts of a URL (Regex)
Given the URL (single line):
http://test.example.com/dir/subdir/file.html
25 Answers
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Check for installed packages before running install.packages() [duplicate]
...
I suggest a more lightweight solution using system.file.
is_inst <- function(pkg) {
nzchar(system.file(package = pkg))
}
is_inst2 <- function(pkg) {
pkg %in% rownames(installed.packages())
}
library(microbenchmark)
microbenchmark(is_inst("aaa"), is_inst2("aaa...
What's the best strategy for unit-testing database-driven applications?
...t database schema after a check out. In addition, keep sample data in data files that get loaded by part of the build process. As you discover data that causes errors, add it to your sample data to check that errors don't re-emerge.
Use a continuous integration server to build the database schema, ...
How can I override Bootstrap CSS styles?
...s to fit my website. I feel it's better to create a separate custom.css file instead of modifying bootstrap.css directly, one reason being that should bootstrap.css get an update, I'll suffer trying to re-include all my modifications. I'll sacrifice some load time for these styles, but it's n...
base64 encoded images in email signatures
...ndary
Content-Type: image/png; name="sig.png"
Content-Disposition: inline; filename="sig.png"
Content-Transfer-Encoding: base64
Content-ID: <0123456789>
Content-Location: sig.png
base64 data
--boundary
And, the HTML part would reference the image like this:
<img src="cid:0123456789">...
Advantages of Antlr (versus say, lex/yacc/bison) [closed]
...ce you have a conflict free grammar, you can let ANTLRworks parse an input file of your language and build a parse tree and AST for you and show the tree graphically in the IDE. This is a very big advantage because it can save you many hours of work: You will find conceptual errors in your language ...
UnicodeDecodeError: 'ascii' codec can't decode byte 0xef in position 1
...decode('utf-8')
>>> print s1
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode characters in position 1-5: ordinal not in range(128)
>>>
Consult the docs for your linux variant to discover how to m...
How to get the path of the batch script in Windows?
... that %0 contains the full path of the batch script, e.g. c:\path\to\my\file\abc.bat
7 Answers
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Windows path in Python
...lways select the correct configuration for your OS:
os.path.join(mydir, myfile)
From python 3.4 you can also use the pathlib module. This is equivelent to the above:
pathlib.Path(mydir, myfile)
or
pathlib.Path(mydir) / myfile
...
Automatically create an Enum based on values in a database lookup table?
...tedTypes" project is built, it runs itself and generates the "MyEnums.dll" file.
By the way, it helps to change the build order of your project so that "EnumeratedTypes" is built first. Otherwise, once you start using your dynamically generated .dll, you won't be able to do a build if the .dll ever...