Variables

Variables in DDP, as in other languages, are “containers” with names in which values are stored.

Declaration

Variables can be created (or declared) as follows:

<data type with article> <variable name> ist <expression>.

There is a special feature for variables with the data type “Wahrheitswert”.
If you want to declare such variables with an expression, you should use this syntax instead:

Der Wahrheitswert <variable name> ist <true or false>, wenn <expression>.

You can find a list of all data types in the article data types

Examples:

Die Zahl a ist 10.
Die Kommazahl b ist 4,32.
Der Text c ist "Hallo!".
Der Wahrheitswert d ist wahr.
Der Wahrheitswert e ist falsch wenn 1 gleich 1 ist. 

Assignment

Assignment is changing the value of a variable. There are several ways to change variables in DDP.

With the keyword is you can only assign variables to a literal:

a ist 30.

To assign the result of an expression to a variable, Speichere ... in must be used:

Speichere pi durch 2 in b.

Special assignments

There are still some assignment operators that can be used to directly change variables, without having to use them in an expression yourself. In other languages, these are so-called “compound assignements”, i.e. operators like +=, -=, *=, etc. . These operators can be used to make code more readable.

Addition

Erhöhe <variable> um <a>

equivalent to

Speichere <variable> plus <a> in <variable>

Subtraction

Verringere <variable> um <a>

equivalent to

Speichere <variable> minus <a> in <variable>

Multiplication

Vervielfache <variable> um <a>.

equivalent to

Speichere <variable> mal <a> in <variable>

Division

Teile <variable> durch <a>.

equivalent to

Speichere <variable> durch <a> in <variable>

Negation

Negiere <variable>.

equivalent to

Speichere -<variable> in <variable>

or

Speichere nicht <variable> in <variable>

Bitshift

Verschiebe <variable> um <a> Bit nach Links

Verschiebe <variable> um <a> Bit nach Rechts

equivalent to

Speichere <variable> um <a> Bit nach Links verschoben in <variable>

Speichere <variable> um <a> Bit nach Rechts verschoben in <variable>