I have an Object which stores pairs for a find and replace that I perform on up to 1500 Strings at a time.
The Object is populated with pairs using a method that will accept a String and then store this as a property with the value being an automatically assigned base 36 number, like this:
function addShort(long:String):void
{
_pairs[long] = _nextShort;
}
_nextShort returns an automatically incremented value being the subject of .toString(36), so running the above a few times might make _pairs look like this:
_pairs:Object = {
"class": "0",
"testing.objects.TestBlock": "1",
"skin.x": "2",
"skin.y": "3",
...........
"someString": "az1"
};
This Object could realistically end up being really large, having over a couple hundred pairs stored.
I then have a method that will take a "long" String (which will include the Strings I've given to addShort() previously) and return a new String where these have been replaced with their respective short value.
The method looks like this:
public function shorten(long:String):String
{
for(var i:String in _pairs)
long = long.split(i).join(_pairs[i]);
return long;
}
Nice an simple, however in my mind I foresee a massive problem in a case where I might want to "shorten" 2000+ Strings and the _pairs Object has at the same time has over 500 pairs.
That ends up being 1,000,000 iterations all up which obviously doesn't seem very efficient at all.
How can I improve this process significantly?
Based on comments from #kapep I realized what I needed is actually a compression library that will do this work for me.
I stumbled across an LZW compression class within a package called Calista which works great.
I did notice that the compression was really slow, which is understandable, but if there are any suggestions for something quicker I'm open to them.
How about Regular Expressions for replacing String patterns? Catch some code.
Related
So I have to go through a bunch of code to get some data from an iframe. the iframe has a lot of data but in there is an object called '_name'. the first key of name is 'extension_id' and its value is a big long string. the json object is enclosed in apostrophes. I have tried removing the apostrophes but still instead of 'extension_id_output' I get a single curly bracket. the json object looks something like this
Frame {
...
...
_name: '{"extension_id":"a big huge string that I need"} "a bunch of other stuff":"this is a valid json object as confirmed by jsonlint", "globalOptions":{"crev":"1.2.50"}}}'
}
it's a whole big ugly paragraph but I really just need the extension_id. so this is the code I'm currently using after attempt 100 or whatever.
var frames = await page.frames();
// I'm using puppeteer for this part but I don't think that's relevant overall.
var thing = frames[1]._name;
console.log(frames[1])
// console.log(thing)
thing.replace(/'/g, '"')
// this is to remove the apostrophes from the outside of the object. I thought that would change things before. it does not. still outputs a single {
JSON.parse(thing)
console.log(thing[0])
instead of getting a big huge string that I need or whatever is written in extension_id. I get a {. that's it. I think that is because the whole object starts with a curly bracket. this is confirmed to me because console.log(thing[2]) prints e. so what's going on? jsonlint says this is a valid json object but maybe it's just a big string and I should be doing some kind of split to grab whaat's between the first : and the first ,. I'm really not sure.
For two reasons:
object[0] doesn't return the value an object's "first property", it returns the value of the property with the name "0", if any (there probably isn't in your object); and
Because it's JSON, and when you're dealing with JSON in JavaScript code, you are by definition dealing with a string. (More here.) If you want to deal with the object that the JSON describes, parse it.
Here's an example of parsing it and getting the value of the extension_id property from it:
const parsed = JSON.parse(frames[1]._name);
console.log(parsed.extension_id); // The ID
I'm trying to create individual dictionary entries while looping through some input data. Part of the data is used for the key, while a different part is used as the value associated with that key. I'm running into a problem (due to Python's "everything is an object, and you reference that object" operations method) with this as ever iteration through my loop alters the key set in previous iterations, thus overwriting the previously set value, instead of creating a new dict key and setting it with its own value.
popcount = {}
for oneline of datafile:
if oneline[:3] == "POP":
dat1, dat2, dat3, dat4, dat5, dat6 = online.split(":")
datid = str.join(":", [dat2, dat3])
if datid in popcount:
popcount[datid] += int(dat4)
else:
popcount = { datid : int(dat4) }
This iterates over seven lines of data (datafile is a list containing that information) and should create four separate keys for datid, each with their own value. However, what ends up happening is that only the last value for datid exist in the dictionary when the code is run. That happens to be the one that has duplicates, and they get summed properly (so, at least i know that part of the code works, but the other key entries just are ... gone.
The data is read from a file, is colon (:) separated, and treated like a string even when its numeric (thus the int() call in the if datid in popcount).
What am I missing/doing wrong here? So far I haven't been able to find anything that helps me out on this one (though you folks have answered a lot of other Python questions i've run into, even if you didn't know it). I know why its failing; or, i think i do -- it is because when I update the value of datid the key gets pointed to the new datid value object even though I don't want it to, correct? I just don't know how to fix or work around this behavior. To be honest, its the one thing I dislike about working in Python (hopefully once I grok it, I'll like it better; until then...).
Simply change your last line
popcount = { datid : int(dat4) } # This does not do what you want
This creates a new dict and assignes it to popcount, throwing away your previous data.
What you want to do is add an entry to your dict instead:
popcount[datid] = int(dat4)
I have no idea how to check for this. My method(if condition in method) should only work (execute) if the first argument passed in is a string. I know how to check other types, but I can't seem to find anything for checking for a string.
For a hash I would do something like;
if(ref eq 'HASH') {...}
If someone could provide a simple example I'm sure I would be able to apply it to what I'm doing. I will put up the code for the method and an explanation for the whole operational details of the method if needed.
Added Information
This is a method for handling different types of errors in the software, here are the 3 possible input formats:
$class->new("error string message")
$class->new("error string message", code => "UNABLE_TO_PING_SWITCH_ERROR")
$class->new("error string message", code => "UNABLE_TO_PING_SWITCH_ERROR", switch_ip => $ip3, timeout => $timeout)
There will always be an error message string first.
With the 1st case there is also a hashref to an error hash structure that is located in a library,
this method new will go into a template processing if the word "code" exists as an arg. where the longer detailed error message is constructed. (I already have the logic for this).
But I have to add logic so that the error message string is added to the hash, so the output is one hash, and not strings.
The second case is very similar to the first, where there are parameters eg. switch_ip , which are inserted into the string using a similar template processing logic, (already have this too).
So I think the first and second cases can be handled in the same way, but I'm not sure, so separated them in this question.
The last case is just can error message string by itself, which at the minute I just insert it into a one key message hash { message => "error string}.
So after all that how should I be checking or dividing up these error cases, At the minute my idea for the ones with code , is to dump the arguments into a hash and just use something like:
if(exists($param{code}) { doTemplateProcess()...}
I need to ensure that there is a string passed in first though. Which was my original question. Does any of my context information help? I hope I didn't go off the topic of my question, if so I'll open this a new question. Thanks.
Error hash - located in Type.pm
use constant ERROR_CODE => {
UNABLE_TO_PING_SWITCH_ERROR => {
category => 'Connection Error:',
template => 'Could not ping switch %s in %s minutes',
tt => {template => 'disabled'},
fatal => 1,
wiki_page => www.error-solution.com/,
},
}
From comments:
These will be called in the software's code like so
ASC::Builder::Error->new(
"Phase x this occured because y was happening:",
code => UNABLE_TO_PING_SWITCH_ERROR,
switch_ip => $ip3,
timeout => 30,
);
Putting the wisdom of your particular problem aside and channeling Jeff Foxworthy:
If you have a scalar and it's not a reference, you might have a string.
If your non-reference scalar doesn't look like a number, it might be a string.
If your non-reference scalar looks like a number, it can still be a string.
If your non-reference scalar has a different string and number value, it might be a dualvar.
You know that your argument list is just that: a list. A list is a collection of scalar values. A scalar can be a reference or not a reference. I think you're looking for the not a reference case:
die "You can't do that" if ref $first_argument;
Past that, you'd have to do fancier things to determine if it's the sort of value that you want. This might also mean that you reject objects that pretend to be strings through overloading and whatnot.
Perhaps you can make the first argument part of the key-value pairs that you pass. You can then access that key to extract the value and delete it before you use the remaining pairs.
You may easily check only whether the error string is a simple scalar value or a reference. You would do that with ref, but you must consider what you want to do if the first parameter isn't a string
You should write your constructor in the ASC::Builder::Error package along these lines
sub new {
my $class = shift;
my ($error, %options) = #_;
die if ref $error;
bless { string => $error }, $class;
}
This example simply dies, and so kills the program, if it is called with anything other than a simple string or number as the first parameter
You may call it as
ASC::Builder::Error->new('error')
or
ASC::Builder::Error->new(42)
and all will be well. If you try
ASC::Builder::Error->new('message', 'code')
then you will see a warning
Odd number of elements in hash assignment
And you may make that warning fatal
If there is anything more then you should explain
Supporting all of the following is simple:
$class->new("s")
$class->new("s", code => "s")
$class->new("s", code => "s", switch_ip => "s", timeout => "s")
All you need is the following:
sub new {
my ($class, $msg, %opts) = #_;
...
}
You can checks such as the following to examine what the called provided:
if (exists($opts{code}))
if (defined($opts{code}))
if ($opts{code})
Despite saying that the string will always be provided, you now ask how to check if was provided. As such, you are probably trying to perform validation rather than polymorphism. You shouldn't waste your time doing this.
Let's look at the hash reference example you gave. ref($arg) eq 'HASH' is wrong. That returns false for some hash references, and it returns false for some things that act like a reference to a hash. The following is a more proper check:
eval { %$arg; 1 }
The equivalent for strings would be the following:
eval { "$arg"; 1 }
Unfortunately, it will always return true! Every value can act as a string. That means the best thing you can do is simply to check if any argument is provided.
use Carp qw( croak );
croak("usage") if !#_;
It's rare for Perl subs to perform argument validation. Not only is it tricky, it's also expensive. It also provides very little benefits. Bad or missing arguments usually results in exceptions or warnings shortly after.
You might see suggestions to use croak("usage") if ref($arg); (or worse, die if ref($arg);), but keep in mind that those will cause the rejection of perfectly fine objects that overload stringification (which is somewhat common), and they will fail to detect the problem with ASC::Builder::Error->new(code => ...) because code produces a string. Again, performing type-based argument validation is an expensive and buggy practice in Perl.
I am doing 2player game and when I get informations from server, it's in format "topic;arg1;arg2" so if I am sending positions it's "PlayerPos;x;y".
I then use split method with character ";".
But then... I even tried to write it on screen "PlayerPos" was written right, but it cannot be gained through if.
This is how I send info on server:
server.write("PlayerPos;"+player1.x+";"+player1.y);
And how I accept it on client:
String Get=client.readString();
String [] Getted = split(Get, ';');
fill(0);
text(Get,20,20);
text(Getted[0],20,40);
if(Getted[0]=="PlayerPos"){
text("HERE",20,100);
player1.x=parseInt(Getted[1]);
player1.x=parseInt(Getted[2]);
}
It writes me "PlayerPos;200;200" on screen, even "PlayerPos" under it. But it never writes "HERE" and it never makes it into the if.
Where is my mistake?
Don't use == when comparing String values. Use the equals() function instead:
if(Getted[0].equals("PlayerPos")){
From the Processing reference:
To compare the contents of two Strings, use the equals() method, as in if (a.equals(b)), instead of if (a == b). A String is an Object, so comparing them with the == operator only compares whether both Strings are stored in the same memory location. Using the equals() method will ensure that the actual contents are compared. (The troubleshooting reference has a longer explanation.)
I'm fairly new to groovy, looking at some existing code, and I see this:
def timestamp = event.timestamp[]
I don't understand what the empty square brackets are doing on this line. Note that the timestamp being def'd here should receive a long value.
In this code, event is defined somewhere else in our huge code base, so I'm not sure what it is. I thought it was a map, but when I wrote some separate test code using this notation on a map, the square brackets result in an empty value being assigned to timestamp. In the code above, however, the brackets are necessary to get correct (non-null) values.
Some quick Googling didn't help much (hard to search on "[]").
EDIT: Turns out event and event.timestamp are both zero.core.groovysupport.GCAccessor objects, and as the answer below says, the [] must be calling getAt() on these objects and returning a value (in this case, a long).
The square brackets will invoke the underlying getAt(Object) method of that object, so that line is probably invoking that one.
I made a small script:
class A {
def getAt(p) {
println "getAt: $p"
p
}
}
def a = new A()
b = a[]
println b.getClass()
And it returned the value passed as a parameter. In this case, an ArrayList. Maybe that timestamp object has some metaprogramming on it. What does def timestamp contains after running the code?
Also check your groovy version.
Empty list, found this. Somewhat related/possibly helpful question here.
Not at a computer, but that looks like it's calling the method event.timestamp and passing an empty list as a parameter.
The same as:
def timestamp = event.timestamp( [] )