# NATURAL

### From Seo Wiki - Search Engine Optimization and Programming Languages

**NATURAL** is a fourth-generation programming language from Software AG. It is largely used for building databases output in plain text form, for example.

* Hello World in NATURAL WRITE 'Hello World!' END

It has the `ESCAPE TOP`

flow control instruction, which is similar to `continue`

in C, C++, Java and other several languages, except that it also works within subroutines to both return from the routine and then continue the calling statement's processing loop.

Like `continue`

, it avoids large amounts of indentation levels when using
nested instruction blocks inside any loop.

Example with ESCAPE TOP:

DEFINE DATA LOCAL 1 I (N3) /* 3 digits without decimals END-DEFINE FOR I = 2 TO 100 IF (I / 2 * 2) = I AND I > 2 WRITE 'Number' I 'is divisible by 2' ESCAPE TOP END-IF IF (I / 3 * 3) = I AND I > 3 WRITE 'Number' I 'is divisible by 3' ESCAPE TOP END-IF IF (I / 5 * 5) = I AND I > 5 WRITE 'Number' I 'is divisible by 5' ESCAPE TOP END-IF IF (I / 7 * 7) = I AND I > 7 WRITE 'Number' I 'is divisible by 7' ESCAPE TOP END-IF IF (I / 11 * 11) = I AND I > 11 WRITE 'Number' I 'is divisible by 11' ESCAPE TOP END-IF WRITE 'Number' I 'is prime' END-FOR END

The levels of indentation can be automatically adjusted with the STRUCT command in the Natural Editor.

The same example, without ESCAPE TOP:

DEFINE DATA LOCAL 1 I (N3) /* 3 digits without decimals END-DEFINE FOR I = 2 TO 100 IF (I / 2 * 2) = I AND I > 2 WRITE 'Number' I 'is divisible by 2' ELSE IF (I / 3 * 3) = I AND I > 3 WRITE 'Number' I 'is divisible by 3' ELSE IF (I / 5 * 5) = I AND I > 5 WRITE 'Number' I 'is divisible by 5' ELSE IF (I / 7 * 7) = I AND I > 7 WRITE 'Number' I 'is divisible by 7' ELSE IF (I / 11 * 11) = I AND I > 11 WRITE 'Number' I 'is divisible by 11' ELSE WRITE 'Number' I 'is prime' END-IF END-IF END-IF END-IF END-IF END-FOR END

Another powerful flow control instruction command is the `ESCAPE BOTTOM`

, which is similar to `ESCAPE TOP`

except that it continues the processing from end of the calling statement's processing loop.
Example with ESCAPE BOTTOM:

DEFINE DATA LOCAL 1 I (N3) /* 3 digits without decimals END-DEFINE FOR I = 2 TO 100 IF (I / 2 * 2) = I AND I > 2 WRITE 'Number' I 'is divisible by 2' ESCAPE BOTTOM END-IF IF (I / 3 * 3) = I AND I > 3 WRITE 'Number' I 'is divisible by 3' ESCAPE BOTTOM END-IF IF (I / 5 * 5) = I AND I > 5 WRITE 'Number' I 'is divisible by 5' ESCAPE BOTTOM END-IF IF (I / 7 * 7) = I AND I > 7 WRITE 'Number' I 'is divisible by 7' ESCAPE BOTTOM END-IF IF (I / 11 * 11) = I AND I > 11 WRITE 'Number' I 'is divisible by 11' ESCAPE BOTTOM END-IF WRITE 'Number' I 'is prime' END-FOR END