a93febb5b7
* add image and deprecated arrow functions * update locales * map basic.showArrow * map arrow blocks * map & remove arrow images * remove arrow blocks * update locales * remove & patch: rgbw -> rgb button/pin pressed -> button/pin event loudness -> soundLevel * update ts mappings for arrows * add wip ts patch rules * update .blocks files * use Click instead of Down as default in Documentation and tests * patch test.blocks * fix lowercase name tag * update test.blocks * update blocks test files * update blocks test files * format block files * pass blocks file tests * fix ts mapping * fix color.defl value closes https://github.com/microsoft/pxt-calliope/issues/136 * fix ts mappings - add optional spacing at the end of rgbw() - map up to v4.0.19 * add suggested changes * replace innerText by textContent Co-authored-by: JW <gitkraken@juriwolf.de> Co-authored-by: Juri <info@juriwolf.de>
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Local Variables
How to define and use local variables.
@parent language
A variable is a place where you can store and retrieve data. Variables have a name, a type, and value:
- name is how you'll refer to the variable
- type refers to the kind of data a variable can store
- value refers to what's stored in the variable
Var statement
Use the Block Editor variable statement to create a variable and the assignment operator to store something in the variable.
For example, this code stores the number 2 in the x variable:
let x = 2;
Here's how to define a variable in the Block Editor:
-
Click
variables. -
Change the default variable name if you like.
-
Drag a block type on the right-side of the assignment operator and click the down arrow to change the variable name.
A variable is created for the number returned by the brightness function.
let b = led.brightness();
Using variables
Once you've defined a variable, just use the variable's name whenever you need what's stored in the variable. For example, the following code shows the value stored in counter on the LED screen:
let counter = 1;
basic.showNumber(counter);
To change the contents of a variable use the assignment operator. The following code sets counter to 1 and then increments counter by 10:
let counter = 1;
counter = counter + 10;
basic.showNumber(counter);
Why use variables?
If you want to remember and modify data, you'll need a variable. A counter is a great example:
let counter = 0;
input.onButtonEvent(Button.A, ButtonEvent.Down, () => {
counter = counter + 1;
basic.showNumber(counter);
});
Local variables
Local variables exist only within the function or block of code where they're defined. For example:
// x does NOT exist here.
if (led.brightness() > 128) {
// x exists here
let x = 0;
}
Notes
- You can use the default variable names if you'd like, however, it's best to use descriptive variable names. To change a variable name in the editor, select the down arrow next to the variable and then click "new variable".