.svg)
What is the 4D Pocket
4D Pocket (四次元ポケット) is a 22nd-century gadget from the manga series Doraemon that has a four-dimensional space containing millions of gadgets.
In Gandi IDE, the 4D Pocket extension contains a set of utils to make your coding experience easier.
Best Practices
[ will be attached very soon ]
Modules
The latest version contains five modules:
Module | Description |
💛 General Utils | - Simply return a string
- Get parts of a URL
- Generate a random ID |
⭕️ Regex Utils | Brings regular expressions into Scratch:
-Does a string match a regex rule?
-Returns matches of a regex for a string
-Splits a string by a regex |
📑 Array Utils | Utils for dealing with JSON Arrays:
- Find the differences between two arrays
- Find an object with a specific key in an array
- Find the intersection of two arrays
- Remove duplicate items in an array
- Concat arrays
- Sort items in an array and sort the objects in an array by a specific key |
📐 Math Utils | Simple useful snippets |
📈 Event Utils | Broadcast and listen to an event with customizable data |
Functions and Definitions
💛 General Utils
This module will include syntactic sugar and useful code snippets for Scratch.
Return a string
Get a static string.
It is the same as this:
In 4D Pocket, it can be used to match a regex (as will be explained in the next module).
Get a part of the current URL
Take the URL `https://cocrea.world/@wangjiaming/PicosworldMMO?kontakt=ZGF0YQ%3D%3D#main` as an example:
Part | Description | Example Value |
href | the full location of the URL | https://cocrea.world/@wangjiaming/PicosworldMMO?kontakt=ZGF0YQ%3D%3D#main |
host | the host of the URL | cocrea.world |
pathname | the path of the URL | /@wangjiaming/PicosworldMMO |
search | the search part of the URL, starting from the symbol ‘?’ | ?kontakt=ZGF0YQ%3d%3d |
hash | the hash of the URL, starting from the hash symbol ‘#’ | #main |
Q: What is this block for?
A: You can make a game with, for example, a god mode, which can only be enabled by a special URL `https://cocrea.world/@yourname/yourproject?godmode=1 `. Your code can be like this:
Generate a random string
Sometimes you want to generate a random string to store user configurations, to use as an archive code, or simply to represent a user. In that case, this block is for you:
The random ID (a string) contains a-z and 0-9, and is case-sensitive.
⭕️ Regex Utils
Regular expressions are very useful technologies for string-searching, matching, and find and replace.
4D Pocket brings regex into Scratch with many useful patterns.
String Match
If a given string matches with a specific regex, it will return true.
The built-in regex rules are shown in the following:
Rule | Description | Original Pattern | Example true case | Example false case |
is digital | the string must be composed only of the digits 0-9. The period symbol is not included. | /^\d+$/gm | 134
0
000
14132124 | a123
12.0
1,000 |
has a digit | the string contains at least one digit | /\d/gm | a1b
abc0efg | abcd |
has letter | the string contains at least one letter | /[a-zA-Z]/gm | a1
aZ
1AZ | 123
1,000 |
start with a digit | the string starts with a digit | /^\d/gm | 0123
0abc
1z
1 | abc
a1
|
end with a digit | the string ends with a digit | /\d$/gm | abc0
a1
2 | abc
1a |
contains Chinese | the string contains at least one Chinese character | /[\u4e00-\u9fa5]/gm | 中文
a中文
中文z | 123
abc |
an email address | the string is an email address | /^([\w+-]+(?:\.[\w+-]+))@((?:[\w-]+\.)\w[\w-]{0,66})\.([a-z]{2,6}(?:\.[a-z]{2})?)$/gm | a@b.com | a.com
abc
@b.com |
For advanced developers, if you are familiar with regex, you can combine two blocks to use customized regex, as shown below.
For example, the blocks below will match a valid US phone number:
Sample valid strings:
1237774820
(281)123-0380
(979) 123-0970
(281)123-2470
281-123-2452Matches of a regex in a string
It will return a JSON array of the matches of a rule in a string.
For example, the block above returns this value:
["Gandi","is","an","in-browser","IDE","for","creating","and",
"running","Scratch","projects","Es","ist","großartig"]The built-in regex patterns are shown below:
Rule | Description | Example input | Example output |
digits | only match digits | ab12b4c64def | ["12","4","64"] |
numbers | numbers, including +- symbols and dot | ab12b4.123c+64de-1.12f | ["12","4.123","+64","-1.12"] |
english and german words | match words, not letters | Schön means beautiful in German | ["Schön","means","beautiful","in","German"] |
within two single quotation marks | the parts of the string between '' | 'a' and 'b' in 'c', and 'd’ | ["a","b","c","d"] |
Split a string
Regex also can be used to split a string by a specific rule.
The block above returns a value like this, and you can keep or remove empty strings.
Keep
["1","2","3","","a","b","c","","e"]Remove
["1","2","3","a","b","c","e"]Built-in regex patterns include splitting a string by spaces, commas, periods, colons, semicolons, vertical bars |, and digits.
📑 Array Utils
Find Differences
Return the differences between two arrays.
In this case, the block returns ["a","d"].
Find by a k-v pair object in an array
In this case, the input JSON contains three objects, as shown on the left, and the block finds the object whose key "name" equals the value "Shawn”, as shown on the right.
Input
[{"name":"Shawn", "score":80},
{"name":"Arkos", "score":100},
{"name":"yk1boy", "score":90}]Output
{"name":"Shawn","score":80}
Find the intersection
When you run the code above, the block returns ["b","c"].
Remove duplicate items
Example output: ["a","b","c","d",1,2,3]
Concat two arrays
You can choose either just concat or uniquify.
Uniquify
will remove duplicates
["a","b","c","d"]Just concat
simply concatenate
["a","b","c","b","c","d"]Sort items in an array
You can sort the items by ASC or DESC.
ASC
[1,3,200,"a","b","c","d"]DESC
["d","c","b","a",200,3,1]📐 Math Utils
Restrict a number within the range [min, max]
This block is a shortcut to the following code:
If the given number (120) is ≤ 0, return 0; if ≥ 100, return 100. In this case, return 100.
📈 Event Utils
Event-driven programming in Scratch is the most common way for sprites to communicate. But the problem is that Scratch doesn’t support passing a specific value from an event dispatcher to its listeners. Normally, scratchers have to use multiple global variables to pass data.
Now, you can use 4D events, as shown below:
Broadcast an event:
Listen to an event:
You can use eventName and eventData under the hat.
For example, you can listen to a 4D message like this:
And dispatch an event like this:
Change Logs
Version | What’s New |
v0.3 | init launched, added:
- General Utils
- Regex Utils
- Array Utils
- Math Utils
- Event Utils
Shawn at 03.July 2022 |
