# s (substitution) processing code

The s processing code substitutes either
a data value from the referenced attribute or literal text when the
current data value is null or zero.

| System Processors | Select, Update, List |
| --- | --- |
| Code Type | Attribute Defining |
| Dictionary Attributes | Input Conversion, Output Conversion, Correlative |

## Syntax

```
s;attrnum1|text|*;attrnum2|text
```

## Parameter(s)

| attrnum1 | Value to substitute if the attribute value tested is not null or zero. Can be an attribute number or literal text enclosed in single quotes. |
| --- | --- |
| attrnum2 | Value to substitute if the attribute value tested is null. Can be an attribute number or literal text enclosed in single quotes. |
| text | Contains the literal text string. |
| * | Displays the original data value, if it is not null or 0; otherwise, the second argument displays. This feature can be used as the first parameter of an f processing code in the form: ```
fattrnum(s;*;’text’)
``` The asterisk can also be embedded within an a processing code. Substitution is used in an a (algebraic) processing code as an alternative to the then/else construct. |

## Description

The s processing
code returns the value defined by attribute number 2 if the value
for conversion is null or 0; otherwise, the value of attribute number
1 is returned. Both attribute number 1 and attribute number 2 can
be an attribute number or text string.

## Example(s)

These a-correlatives produce
identical results:

```
aif n(sales)>="1000000" then "made it" else "trouble"
```

```
a(n(sales)>="1000000")(s;"made it";"trouble")
```
The following checks for the existence of a shipping address
in attribute 20. If not there, show the billing address in attribute
10.

```
a(20)(S;*;10)
```

## See also

- [a (algebraic) processing code](https://d3codex.com/processingcodes/a-algebraic-processing-code/)
- [Processing codes (Update processor)](https://d3codex.com/updateprocessor/processing-codes-update-processor/)
- [Processing codes overview](https://d3codex.com/processingcodes/processing-codes-overview/)
- [Processing codes (Update processor)](https://d3codex.com/updateprocessor/processing-codes-update-processor/)
- [u009e user exit](https://d3codex.com/pickbasic-flashbasic/u009e-user-exit/)

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Source: https://d3codex.com/processingcodes/s-substitution-processing-code/ - part of the D3Codex reference.