大约有 6,261 项符合查询结果（耗时：0.0179秒） [XML]
Why is whitespace sometimes needed around metacharacters?
...@DmitriChubarov Braces are allowed in command names (including functions: {foo} () { echo hello; }. "Name", as defined in by bash as "a word consisting only of alphanumeric characters and underscores, and beginning with an alphabetic character or an underscore", applies only to var...
java: Class.isInstance vs Class.isAssignableFrom
...
clazz.isAssignableFrom(Foo.class) will be true whenever the class represented by the clazz object is a superclass or superinterface of Foo.
clazz.isInstance(obj) will be true whenever the object obj is an instance of the class clazz.
That is:
c...
How to implement an abstract class in ruby?
...o
@klass = Class.new do
extend Abstract
abstract_methods :foo, :bar
end
end
it "raises NoMethodError" do
proc {
@klass.new.foo
}.should raise_error(NoMethodError)
end
it "can be overridden" do
subclass = Class.new(@klass) do
def foo
:ove...
Renaming table in rails
...
You would typically do this sort of thing in a migration:
class RenameFoo < ActiveRecord::Migration
def self.up
rename_table :foo, :bar
end
def self.down
rename_table :bar, :foo
end
end
share
...
C multi-line macro: do/while(0) vs scope block [duplicate]
...ll contexts.
Consider the following code sketch
if (<condition>)
foo(a);
else
bar(a);
where 'foo' and 'bar' are ordinary functions. Now imagine that you'd
like to replace function 'foo' with a macro of the above nature
if (<condition>)
CALL_FUNCS(a);
else
bar(a);
Now, if y...
Python: access class property from string [duplicate]
...ords:
>>> class c:
pass
o = c()
>>> setattr(o, "foo", "bar")
>>> o.foo
'bar'
>>> getattr(o, "foo")
'bar'
share
|
improve this answer
|
...
Converting an array to a function arguments list [duplicate]
...that works, why won't this work? document.body.setAttribute.apply( this, ["foo", "bar"] ); I need to send variable arguments to various object methods with different argument requirements. Quick edit: Apparently this has to be document.body, or whatever the parent is
– bryc
...
Ruby ampersand colon shortcut [duplicate]
.... The colon in this case is for the symbol. So, there's & and there's :foo.
The & calls to_proc on the object, and passes it as a block to the method. In Rails, to_proc is implemented on Symbol, so that these two calls are equivalent:
something {|i| i.foo }
something(&:foo)
Also, to_pro...
Run jar file in command prompt [duplicate]
...f you dont have an entry point defined in your manifest invoking java -jar foo.jar will not work.
Use this command if you dont have a manifest or to run a different main class than the one specified in the manifest:
java -cp foo.jar full.package.name.ClassName
See also instructions on how to cre...
How to assign multiple classes to an HTML container? [closed]
...on order. The names in the class attribute have no specified order, since .foo is syntactic sugar for [class ~= foo] ref, "foo is a word in the class attribute".
– Ulrich Schwarz
Jan 13 '14 at 16:50
...