Obyx

The Instruction Function

Instruction Attributes

Operation:
The instruction's operation indicates how input are processed into the outputs. All inputs are operated on left to right (first to last). The following operations are available.

Basic operations:

• assign*
  Pushes the input data into the output parameters without changing the data. This is the default value for the instruction operation as denoted by the *asterisk and the blue text in the visual guide.

String processing operations:

• append
  Concatenates the data from all the input elements.
• substring
  Returns a substring of an initial input value.
• position
  Returns the index of the first input in the second input.
• length
  Returns the string length of the inputs.
• left
  Returns a specified number of characters from the left side of the first input string. Subsequent inputs determine the number of characters.
• right
  Returns a specified number of characters from the right side of the first input string. Subsequent inputs determine the number of characters.
• lower
  Converts a string into lower case.
• upper
  Converts a string into upper case.

Arithmetic operations: (note: the precision of the outputs of these operations can be set using the precision attribute)

• add
  Performs an arithmetic add across all the input parameters.
• subtract
  Performs an arithmetic subtract across all the input parameters.
• multiply
  Performs an arithmetic multiply across all the input parameters.
• divide
  Performs an arithmetic divide across all the input parameters and pushes the result into the output parameters. Divide is performed accumulatively first to last.
• quotient
  Performs an arithmetic divide across all the input parameters returning the quotient. Arithmetic is performed cumulatively first to last.
• function
  Performs a specific task separately from the main program. Also known as a subroutine or subprogram in other languages.
• remainder
  Performs an arithmetic modulus (remainder) across all the input parameters. Arithmetic is performed cumulatively first to last.
• max
  Returns the maximum value of all input elements.
• min
  Returns the minimum value of all input elements.

Special operations:

• shell
  Executes a server-side script as specified by the inputs.
• query
  Silently executes an SQL statement as specified by the inputs. Returns from the SQL are ignored.

Pecision: (0..16)
All mathematical functions internally occur at the highest precision (16 decimal places). The output is then rounded to the number of decimal places specified. Zero (integer) is the default as denoted by the blue text in the visual guide.

Basic Instruction Examples

Hello World

This basic example simply outputs the string "hello world":

<instruction>
	<input value="hello world" />
</instruction>

hello world

This is a more verbose version of the above example showing where the default values are incorporated:

<instruction operation="assign">
	<output space="immediate" />
	<input value="hello world" />
</instruction>

hello world

Storing date into a store

This examples shows how you would assign a value to a store:

<instruction operation="="assign">
	<output space="store" value="myVar"/>
	<input value="pigeon" />
</instruction>

the store "myVar" contains "pigeon"

Arithmetic example: Adding numbers together

This example shows the instruction function being used to arithmetically add together a number of inputs:

<instruction operation="add">
	<input value="2" />
	<input value="3" />
	<input value="4" />
</instruction>

9

String processing example: Trimming a string

This example shows how the "right" string processing operation is used to trim a string:

<instruction operation="right">
	<input value="Hippopotamus" />
	<input value="8" />
</instruction>

opotamus

Further examples can be found within the documentation for each operation.