I have this function written in CoffeeScript that I feel should be better written:
addCSS = (files) ->
i = files.length - 1
while i >= 0
$("<link/>",
rel: "stylesheet"
href: files[i]
).appendTo $("head")
i--
return
The files arg is just an array of file paths.
Is there a more succinct/cleaner way to write this in CoffeeScript?
A simple
addCSS = (files) ->
for file in files
$("<link/>",
rel: "stylesheet"
href: file
).appendTo $("head")
(no need for return either, although it does prevent coffee from returning a bunch of stuff)
In case you are wondering, because of the horrible behavior of JS with for ... in loop, it is compiled as
for (_i = 0, _len = files.length; _i < _len; _i++) {
file = files[_i];
// ...
}
Edit
I realize just now that you are reversing the array, so it would be
for file in files by -1
(supported since 1.5.0)
compiles as for (_i = files.length - 1; _i >= 0; _i += -1) {
Related
I made a 5 second time bar to replace the wave. when wave1 has been 5 seconds it will move to wave2. then the first wave will be destroyed. when I got to wave3, an error came out. here's my code:
IEnumerator ChangeWave()
{
for (int i = 0; i < wave.Length - 1; i++)
{
yield return new WaitForSeconds(5f);
Destroy(wave[i]);
wave[i+1].SetActive(true);
}
}
the error said The object of type 'GameObject' has been destroyed but you are still trying to access it. - unity
sorry for my bad english.
There's a few things going on here.
Remove the -1 in the for loop, so it iterates to end
wave[i+1] will cause an error, so check if (i < wave.Length -1)
Destroy( array[index] ) will try and access Game Object but it's destroyed, so you should create a temporary var to hold gameobject, and set null to the array element.
Some fixes below - there might be a better way, but this is what I use:
Version 1 - Using the above fixes
IEnumerator ChangeWaveV2()
{
for (int i = 0; i < wave.Length; i++)
{
yield return new WaitForSeconds(.2f);
var t = wave[i];
wave[i] = null;
Destroy(t);
if(i < wave.Length - 1)
wave[i + 1].SetActive(true);
}
}
Version 2 - A variation without needing to null out the element and create a temporary var. If you iterate from end to front of the array, you can freely Destroy() GameObjects in an array. May not be useful as it changes the wave array.
IEnumerator ChangeWaveV3()
{
System.Array.Reverse(wave);
for (int i = wave.Length - 1; i >= 0; i--)
{
yield return new WaitForSeconds(.2f);
Destroy(wave[i]);
if(i > 0)
wave[i - 1].SetActive(true);
}
}
I try to change an array of user in my mongodb from another collection.
this is the code:
phrases.find({albumID: tileid}).toArray(function(err, results) {
if (results.length > 0) {
for(var j = 0; j < results.length; j++)
{
for(var z = 0; z < o.Phrases.length; z++)
{
if(o.Phrases[z].id == results[j]._id)
{
o.Phrases.splice(z,1);
break;
}
}
}
}
});
console.log(o.Phrases);
.
.
.
after update the collection
When I do logs, I don't see the change being made.
If I do the logs in toArray blocks, I see the changes.
I read alot, And dont found solution only that toArray is async function but not how to change it or to use it.
Maybe there is another way to change the collection to the array.
thanks for helping.
I am trying to generate some DXL documentation usings Doxygen , but the results are often not correct , DXL is used as a scripting language and that has a C/C++ like syntax with some changes , like for example i can ignor using the Semicolons , What should i do to correct this problem ?
which creates some problems while generating the documentation, here is an example of my dxl code database :
string replace (string sSource, string sSearch, string sReplace) {
int iLen = length sSource
if (iLen == 0) return ""
int iLenSearch = length(sSearch)
if (iLenSearch == 0) {
return ""
}
char firstChar = sSearch[0]
Buffer s = create()
int pos = 0, d1,d2;
int i
while (pos < iLen) {
char ch = sSource[pos];
bool found = true
if (ch != firstChar) {pos ++; s+= ch; continue}
for (i = 1; i < iLenSearch; i++) {
if (sSource[pos+i] != sSearch[i]) { found = false; break }
}
if (!found) {pos++; s+= ch; continue}
s += sReplace
pos += iLenSearch
}
string result = stringOf s
delete s
return result }
as i said the main difference with C and that may cause doxygen to interpret this code incorrectly is that in DXL , we dont have to use ";" .
thanks in advance
You must do three things to apply Doxygen successfully on DXL scripts:
1.) In Doxygen-GUI, 'Wizard' tab, section 'Mode' choose 'Optimize for C or PHP'
2.) The DXL code must be C-confom, i.e. each statement ends with a semicolon ';'
3.) In tab 'Expert' set language mapping for DXL and INC files in section 'Project' under 'EXTENSION_MAPPING':
dxl=C
inc=C
This all tells Doxygen to treat DXL scripts as C code.
Further, for DOORS to recognize a DXL file documented for DoxyGen as valid and bind it to a menu item, it must comply with certain header structure, consisting of single line and multi-line comment, e.g.
// <dxl-file>
/**
* #file <dxl-file>
* #copyright (c) ...
* #author Th. Grosser
* #date 01 Dec 2017
* #brief ...
*/
I have objects like:
{ "_id" : ObjectId( "4e00e83608146e71e6edba81" ),
....
"text" : "Text now exists in the database"}
and I can add hash fields through java using the com.mongodb.util.Hash.longHash method to create
{ "_id" : ObjectId( "4e00e83608146e71e6edba81" ),
....
"text" : "Text now exists in the database",
"tHash" : -4375633875013353634 }
But this is quite slow. I would like to be able to do something within the database like:
db.foo.find( {} ).forEach( function (x) {
x.tHash = someFunction(x.text); // create a long hash compatible with com.mongodb.util.Hash.longHash
db.foo.save(x);
});
Does anyone know how I can call this long hash within the Javascript function?
First define a nice hashCode function to use. JavaScript does not have a hashCode function by default on all objects so you will need to write one. Or just use this one:
var hashCode = function(s) {
if (s == null) return 0;
if (s.length == 0) return 1;
var hash = 0;
for (var i = 0; i < s.length; i++) {
hash = ((hash << 5) - hash) + s.charCodeAt(i);
hash = hash & hash; // Convert to 32bit integer
}
return hash;
};
Alternatively use another hash function like MD5 - there are scripts that can generate them for you.
I gave up trying to replicate the Mongo Java driver Hash.longHash method in Javascript, since JS treats everything as a float and doesn't handle the overflow like Java does. I found some examples of replicating the Java hashCode function in JS and so I did this:
longHash = function(s){
var hash = 0;
if (s.length == 0) return hash;
for (i = 0; i < s.length; i++) {
char = s.charCodeAt(i);
hash = ((hash<<5)-hash)+char;
hash = hash & hash; // Convert to 32bit integer
}
return NumberInt(hash);
};
db.foo.find( {} ).forEach( function (x) {
x.cHash = longHash(x.c);
db.foo.save(x);
});
which at least let me do a integer level hash code on the existing data. This will be enough to narrow down data for indexing.
Update: I just updated with by returning a NumberInt type instead. By default the hash was a Javascript number and was stored in Mongo as a Double taking much more space than necessary. The NumberInt is a 32-bit signed integer, and NumberLong is a 64-bit version.
I am new to python, I have looked at boost python, and it looks very
impressive. However going through the introduction I can not find
any examples where, vector of objects are returned as python list/tuples.
i.e Take this example, I want to expose class X, Cont and all its functions.
critical bit being return a vector of X's or strings to python
class X {};
class Cont {
.....
// how can this be exposed using boost python
const std::vector<X>& const_ref_x_vec() const { return x_vec_;}
std::vector<X> value_x_vec() const { return x_vec;}
const std::vector<std::string>& const_ref_str_vec() const { return str_vec_;}
std::vector<std::string> value_str_vec() const { return str_vec_; }
...
private:
std::vector<X> x_vec_;
std::vector<std::string> str_vec_;
};
My own fruitless attempt at trying to expose the functions like
const_ref_x_vec(), value_x_vec(),etc just leads to compile errors.
from googling around I have not seen any example that support returning vectors
by value or reference. Is this even possible with boost python?
are there any workarounds ? should I be using SWIG for this case ?
Any help appreciated.
Avtar
Autopulated's reason was essentially correct, but the code was more complicated then necessary.
The vector_indexing_suite can do all that work for you:
class_< std::vector<X> >("VectorOfX")
.def(vector_indexing_suite< std::vector<X> >() )
;
There is a map_indexing_suite as well.
Because you can't expose template types to python you have to explicitly expose each sort of vector that you want to use, for example this is from my code:
Generic template to wrap things:
namespace bp = boost::python;
inline void IndexError(){
PyErr_SetString(PyExc_IndexError, "Index out of range");
bp::throw_error_already_set();
}
template<class T>
struct vec_item{
typedef typename T::value_type V;
static V& get(T& x, int i){
static V nothing;
if(i < 0) i += x.size();
if(i >= 0 && i < int(x.size())) return x[i];
IndexError();
return nothing;
}
static void set(T& x, int i, V const& v){
if(i < 0) i += x.size();
if(i >= 0 && i < int(x.size())) x[i] = v;
else IndexError();
}
static void del(T& x, int i){
if(i < 0) i += x.size();
if(i >= 0 && i < int(x.size())) x.erase(x.begin() + i);
else IndexError();
}
static void add(T& x, V const& v){
x.push_back(v);
}
};
Then, for each container:
// STL Vectors:
// LineVec
bp::class_< std::vector< Line > >("LineVec")
.def("__len__", &std::vector< Line >::size)
.def("clear", &std::vector< Line >::clear)
.def("append", &vec_item< std::vector< Line > >::add,
bp::with_custodian_and_ward<1, 2>()) // let container keep value
.def("__getitem__", &vec_item< std::vector< Line > >::get,
bp::return_value_policy<bp::copy_non_const_reference>())
.def("__setitem__", &vec_item< std::vector< Line > >::set,
bp::with_custodian_and_ward<1,2>()) // to let container keep value
.def("__delitem__", &vec_item< std::vector< Line > >::del)
.def("__iter__", bp::iterator< std::vector< Line > >())
;
// ...
A similar approach is possible for std::map.
I used lots of help from wiki.python.org when writing this.