小编Mic*_*ker的帖子

class A{
  A(int a = 5){
    DoSomething();
    A();
  }
  A(){...}
}

第一个构造函数可以调用第二个构造函数吗？

你能告诉我当我尝试'git apply-patch'时如何解决'补丁不适用'错误？

$ git apply 0001-my.patch
error: patch failed:test.xml:114
error: text.xml: patch does not apply

我的本地目录中有'test.xml'.当我做'git status'时,它表明我没有本地更改.

感谢您的任何帮助.

在我的代码的第一部分中,我读取了一个文件并将其中的不同部分存储在目录中的不同文件中,并且在下面我想读取该目录中我在代码的第一部分构建它的所有文件:

while(<file>){

#making files in directory Dir

}

opendir(Dir, $indirname) or die "cannot open directory $indirname";
@docs = grep(/\.txt$/,readdir(Dir));
foreach $d (@Dir) {
    $rdir="$indirname/$d";
    open (res,$rdir) or die "could not open $rdir";
    while(<res>){


}

但是使用此代码,最后一个文件的最后一行不会被读取

我正在使用FMDB包装器我使用此代码

- (BOOL)update:(NSString *) Body fromValue:(NSString *)froms {

    BOOL success = NO;
    FMResultSet *rs;
//I have **searchTable** and in that folder name **OFFICE**  

    rs = [self.database executeQuery:@"select searchId,body from searchTable WHERE folder = 'OFFICE'"];


    NSInteger primaryKey = -1;
    NSString *body = nil;
    NSString *md5OfSearchEmailBody = nil;
    while ([rs next]) {
        primaryKey  = [rs intForColumn:@"searchId"];
        body = [rs stringForColumn:@"body"];
    }           

    [rs close];
    return success;
}

第一次

- (BOOL)update:(NSString *) Body fromValue:(NSString *)froms{
}

方法工作正常.在循环第二次它不工作

调用sqlite3_step(21:out of memory)rs时出错

如何解决这个问题呢

Windows 2.6 of Python 2.6.4:有没有办法确定使用shell = True时subprocess.Popen()是否失败？

当shell = False时,Popen()成功失败

>>> import subprocess
>>> p = subprocess.Popen( 'Nonsense.application', shell=False )
Traceback (most recent call last):
  File ">>> pyshell#258", line 1, in <module>
    p = subprocess.Popen( 'Nonsense.application' )
  File "C:\Python26\lib\subprocess.py", line 621, in __init__
    errread, errwrite)
  File "C:\Python26\lib\subprocess.py", line 830, in
_execute_child
    startupinfo)
WindowsError: [Error 2] The system cannot find the file specified

但是当shell = True时,似乎无法确定Popen()调用是否成功.

>>> p = subprocess.Popen( 'Nonsense.application', shell=True )
>>> p
>>> subprocess.Popen object at 0x0275FF90>>>
>>> …

我想声明一个指向objective-c中指针的指针.

我有一个实例变量(primaryConnection),它应该动态更新,以便在更改时指向局部变量.

NSURLConnection *primaryConnection;

-(void) doSomething
{
  NSURLConnection *conn;
  primaryConnection = conn;

  conn = // set by something else

  // primaryConnection should now reflect the pointer that conn is pointing to, set by something else... but it doesn't?
}

是否有可能以某种方式声明指针指针？或者我错过了什么？