63 lines
1.4 KiB
Markdown
63 lines
1.4 KiB
Markdown
# Sequencing
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By calling one function after another, in sequence, you can create an animation:
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```typescript
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basic.showLeds(`
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. # . # .
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. . . . .
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. . # . .
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# . . . #
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. # # # .
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`);
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basic.showLeds(`
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. # . # .
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. . . . .
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. . . . .
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. # # # .
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# . . . #
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`);
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```
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### The semicolon
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In JavaScript, the semicolon (;) is used to terminate (or end) a statement. However, in most
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cases, the semicolon is optional and can be omitted. So both code sequences below are
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legal:
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```typescript
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basic.showNumber(1)
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basic.showNumber(2)
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```
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```typescript
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basic.showNumber(1);
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basic.showNumber(2);
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```
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## The empty statement
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In JavaScript, there is the concept of an *empty statement*, which is whitespace followed by
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a semicolon in the context where a statement is expected.
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So, the following code is an infinite loop
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followed by a call to `showNumber` that will never execute:
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```typescript
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while(true) ;
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basic.showNumber(1);
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```
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### ~hint
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For the micro:bit, we don't allow a program to contain an empty statement, such as shown above.
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If you really want an empty statement, you need to use curly braces to delimit an empty statement block:
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```typescript
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while(true) { }
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basic.showNumber(1);
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```
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### ~
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[Read more](http://inimino.org/~inimino/blog/javascript_semicolons) about semicolons in JavaScript.
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### ~button /js/variables
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NEXT: Variable Declarations
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### ~ |