alias

问题 This question was inspired in part by this one. alias foo='ls -1 $1' foo /etc displays the contents of /etc, one item per line. ls -1 /etc | tail displays the last ten items in /etc. But alias foo='ls -1 $1 | tail' foo /etc displays: tail: error reading `/etc': Is a directory 回答1: I have found variable expansion in aliases to be flaky, and not recommended: http://www.gnu.org/software/bash/manual/bashref.html#Aliases Use a function instead: function foo() { ls -1 $1; } 回答2: Aliases done this

问题 Let say I have a basic 2D vector class something like class vector2 { int x, y; } these two values could be used to represent a position as well as a width and height. does C++ provide a away for me to impliment a function such as vector2::getXpos() and then also define vector2::getWidth() and have it use the same implementation. I know that I could just make both of these function inline, but the compiler might decide to not inline these functions. so if getWidth just called getXpos you

问题 I have a query SELECT COUNT(*) AS "CNT", imei FROM devices which executes just fine. I want to further restrict the query with a WHERE statement. The (humanly) logical next step is to modify the query followingly: SELECT COUNT(*) AS "CNT", imei FROM devices WHERE CNT > 1 However, this results in a error message ORA-00904: "CNT": invalid identifier . For some reason, wrapping the query in another query produces the desired result: SELECT * FROM (SELECT COUNT(*) AS "CNT", imei FROM devices

问题 Can someone tell me how Python "aliases" os.path to ntpath ? >>> import os.path >>> os.path <module 'ntpath' from 'C:\Python26\lib\ntpath.pyc'> >>> 回答1: Look at os.py, lines 55-67: elif 'nt' in _names: name = 'nt' linesep = '\r\n' from nt import * try: from nt import _exit except ImportError: pass import ntpath as path import nt __all__.extend(_get_exports_list(nt)) del nt The import ntpath as path is the specific statement that causes os.path to be ntpath on your platforms (doubtlessly

问题 I am attempting to set up aliases for my Cygwin bash shells, to run programs contained in the standard Windows C:\Program Files subdirectories. Unfortunately, the alias command really doesn't like spaces in a directory name, and nothing I've tried seems to work. I'm trying to get the following running: alias npp='/cygdrive/c/Program Files/Notepad++/notepad++.exe' I am currently cheating and using a soft link, but I would prefer to use an alias. 回答1: Escape Characters: alias npp="/cygdrive/c

问题 Lets say i have this search term: grep -i -r --include=*.xib "img_28301.png" ./ how would i go about creating an alias that allows me to do this: xibsearch img_28301.png and do the same thing? 回答1: It will be much cleaner to have a function for this: xibsearch() { grep -i -r --include=*.xib "$1" ./ } As alias doesn't support positional parameters. 回答2: As @anubhava points out, functions are generally the way to go here. However, in this case, if you really must use an alias, you can rearrange

问题 I don't know where to begin to debug this. Some developers have been writing some pl/sql code locally on their Windows machines that complete fine using Oracle 10.2.0.1.0 - 64bit. When it gets to production, which is Red Hat 5.3 and running 10.2.0.2.0, it gives me this error: ORA-00904: "S"."BARSTREAMREFERENCEID": invalid identifier Here is the gist of the code that is working in Windows: EXECUTE IMMEDIATE(' update candyman.CANDY_REFERENCES s set ( s.flavour, s.taste, s.colour, s

问题 How does SQLite internally treats the alias? Does creating a table name alias internally creates a copy of the same table or does it just refers to the same table without creating a copy? When I create multiple aliases of the same table in my code, performance of the query is severely hit! In my case, I have one table, call it MainTable with namely 2 columns, name and value. I want to select multiple values in one row as different columns. for example Name: a,b,c,d,e,f Value: p,q,r,s,t,u such

问题 I am writing custom Powershell cmdlets for my application and I need to provide Aliases to some cmdlets. So lets say I have cmdlet Get-DirectoryListing and I want to add Alias (say 'gdl') to this cmdlet. How can I do this? The AliasAttribute doesn't work here, since it works only with Properties, Indexers or Field declarations. Also I know we can use Set-Alias command, but don't know where to put it. Is it possible to programmatically add multiple aliases to a cmdlet? 回答1: You need to create

问题 I would like to "rename" some members of my class ofVec4f . I know it's impossible in strict C++ but could I create a new class that inherits from my class and declare new members which are aliases or pointers to the original members? I tried the following: class ofVec4fGraph : public ofVec4f { public : float& minX; float& maxX; float& minY; float& maxY; ofVec4fGraph(float _minX,float _maxX, float _minY, float _maxY ) : minX(_minX), maxX(_maxX), minY(_minY), maxY(_maxY) { ofVec4f(_minX, _maxX