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## Values

### Numbers

0 345 12.34 0.12345

Normal real numbers.

### Boolean values

true false

True or false as value. In numerical expressions such as **true** + 1 and **false** x 5 - 2, **true** and **false** are taken as 1 and 0 respectively. However, as of v0.12m of Danmakufu, they cannot be compared with other numerical expressions, e.g. conditionals like **true** == 1 and **false** > 0 will not parse.

### Characters

'A' 'E' 'あ'

One letter. Japanese character can be used.

### Arrays

[3, 1, 4, 1, 5, 9] [true, false, true, true, false]

Array of values. Multidimensional arrays can be used, e.g.

let Array = [ [3, 1, 4], [1, 5, 9] ];

the entry Array[1][2] will then have the value 9. To change the value of Array[1][2], v0.12m of Danmakufu will not parse

Array[1][2] = 8; //this is wrong

One way to do this is

Array[1] = [1, 5, 8]; //this is correct

i.e. you can only change entries that are one level deep. 'Mixed-entry' arrays are not allowed, e.g.

Array = [ [3, 1, 4], [1, 5] ]; //these are wrong Array2 = [ [3, 1, 4], 1 ];

will not parse. The entries in an array must all be of the same kind.

You can concantenate arrays

[3, 1, 4] ~ [1, 5, 9];

this gives the single array

[3, 1, 4, 1, 5, 9]

You can also erase entries from arrays

erase([3, 1, 4, 1, 5, 9], 2);

this gives the shortened array

[3, 1, 1, 5, 9]

### Strings

"Hello, world!" "Test Sign 'Test'" "試符「テスト」"

Arrays of characters.

\"

describes a string literal which contains only a letter ".

## Variable Definitions

let ImgBoss = "script\img\ExRumia.png"; let frame = -120; let array = [3, 1, 4, 1, 5, 9];

Variables are storages of values. **let** is used to define variables.

let (variable name); let (variable name) = (initial value);

The variable name consists of alphabets, figures, and underscore (_), but it cannot begin with figures. The initialization of the variable can be omitted.

## Expressions

### Numerical Expressions

6 * 2 + (4 - 3) * 9 x ^ 2 + 3 % x + 8

Standard numerical expressions. The priority of operators is common-sense. Variables can be used in the expressions.

### Conditional Expressions

frame == 10 ! (x < y && y < z)

Standard conditional expressions. The results of the conditional expressions are boolean values. Note that "if equal" is not '=' but '=='. For the meanings of the operators, refer to the *Priority of Operators* subsection.

### Indexing Expressions

[3, 1, 4, 1, 5, 9][2] array[i]

Get an element of the array with the index.

array[1..4]

A slice of the array can be extracted.

(array)[(index)] (array)[(first index)..(last index)]

### Array Calculations

[3, 1, 4] + [1, 5, 9] array1 + array2

Each element is calculated, e.g. [3, 1, 4] + [1, 5, 9] is [4, 6, 13].

### String Expressions

"script\img\ExRumia.png" ImgFolder ~ "ExRumia.png"

Operator '~' concatenates two arrays (of course strings, too). String leterals can be concatenated without ~ operators as

"Wave Sign " \" "Mind Shaker" \"

which is such a string as

Wave Sign "Mind Shaker"

### Priority of Operators

High Priority

#### ( )

Parentheses#### (| |)

Absolute value#### [ ]

Indexing, Slicing#### ^

Power#### +

Plus sign#### -

Minus sign#### !

Conditional not#### *

Multiplication#### /

Division#### %

Modulo (Remainder)#### +

Addition#### -

Subtraction#### ~

Concatenation#### ==

Equal to#### !=

Not equal to#### <

Less than#### <=

Less than or equal to#### >

Greater than#### >=

Greater than or equal to#### &&

Conditional and#### ||

Conditional or

Low Priority

## Assignment Statements

### Simple Assignment Statements

y = x ^ 2 + 3 * x + 8; frame = 0; array[2] = 4;

Change the left-side variable contents with right value.

(variable) = (expression);

### Compound Assignment Statements

x += 3; y *= 2;

Operate right value to the left-hand variable and assign the result into the variable. e.g.

x += 3;

adds 3 to x, and

y *= 2;

multiplies 2 to y.

(variable) (binary numerical operator)= (expression);

### Increment/Decrement

frame++;

Add 1 to the variable.

i--;

Subtract 1 from the variable.

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