大约有 48,000 项符合查询结果（耗时：0.0502秒） [XML]
Determine if Python is running inside virtualenv
...t reliable way to check for this is to check whether sys.prefix == sys.base_prefix. If they are equal, you are not in a virtual environment; if they are unequal, you are. Inside a virtual environment, sys.prefix points to the virtual environment, and sys.base_prefix is the prefix of the system Pytho...
In pure functional languages, is there an algorithm to get the inverse function?
...he functional languages have that option. For example:
f :: a -> Int
f _ = 1
This function does not have an inverse.
share
|
improve this answer
|
follow
...
dispatch_after - GCD in Swift?
...
A clearer idea of the structure:
dispatch_after(when: dispatch_time_t, queue: dispatch_queue_t, block: dispatch_block_t?)
dispatch_time_t is a UInt64. The dispatch_queue_t is actually type aliased to an NSObject, but you should just use your familiar GCD methods t...
Manually map column names with class properties
...
This works fine:
var sql = @"select top 1 person_id PersonId, first_name FirstName, last_name LastName from Person";
using (var conn = ConnectionFactory.GetConnection())
{
var person = conn.Query<Person>(sql).ToList();
return person;
}
Dapper has no facilit...
Instance variables vs. class variables in Python
...test:
import timeit
setup='''
XGLOBAL= 5
class A:
xclass = 5
def __init__(self):
self.xinstance = 5
def f1(self):
xlocal = 5
x = self.xinstance
def f2(self):
xlocal = 5
x = A.xclass
def f3(self):
xlocal = 5
x = XGLOBAL
...
How do I remove code duplication between similar const and non-const member functions?
...& get() const {
return c;
}
char & get() {
return const_cast<char &>(static_cast<const C &>(*this).get());
}
char c;
};
The two casts and function call may be ugly but it's correct. Meyers has a thorough explanation why.
...
Is there a way to auto expand objects in Chrome Dev Tools?
...creatively (ab)using console.group:
expandedLog = (function(){
var MAX_DEPTH = 100;
return function(item, depth){
depth = depth || 0;
if (depth > MAX_DEPTH ) {
console.log(item);
return;
}
if (_.isObject(item)) {
_.e...
Can I use a min-height for table, tr or td?
...e width="100%" cellspacing="0" class="htmlgrid-table">
<tr id="tr_0">
<td width="3%" align="center" class="readOnlyCell rowNumberColumn">1</td>
<td align="left" width="40%" id="td_0_0" class="readOnlyCell gContentSection">411978430-Intimate:Ruby...
What exactly does git's “rebase --preserve-merges” do (and why?)
...B --not $(git merge-base --all A B)
Replay the commits:
Create a branch B_new, on which to replay our commits.
Switch to B_new (i.e. "git checkout B_new")
Proceeding parents-before-children (--topo-order), replay each commit c in C on top of B_new:
If it's a non-merge commit, cherry-pick a...
Liquibase lock - reasons?
...l="CONTINUE">
<not><sequenceExists sequenceName="SEQUENCE_NAME_SEQ" /></not>
</preConditions>
<createSequence sequenceName="SEQUENCE_NAME_SEQ"/>
</changeSet>
A work around is using plain SQL to check this instead:
<changeSet author="user...