mirror of
https://github.com/QB64Official/qb64.git
synced 2024-08-22 11:25:08 +00:00
47 lines
1.1 KiB
Markdown
47 lines
1.1 KiB
Markdown
|
The [_ASSERT](_ASSERT) statement can be used to perform tests in code that's in development, for debugging purposes.
|
||
|
|
||
|
## Syntax
|
||
|
|
||
|
> [_ASSERT](_ASSERT) condition[, errorMessage$]
|
||
|
|
||
|
## Description
|
||
|
|
||
|
* condition is the condition that must be met in order to consider the _ASSERT valid.
|
||
|
* Optional errorMessage$ is the message to be displayed in the console window if [$ASSERTS]($ASSERTS) is used.
|
||
|
* If the condition is not met (that is, if it evaluates to 0), an error occurs ("_ASSERT failed on line #") and program execution stops.
|
||
|
|
||
|
## Availability
|
||
|
|
||
|
* Version 1.4 and up.
|
||
|
|
||
|
## Example(s)
|
||
|
|
||
|
Adding test checks for parameter inputs in a function.
|
||
|
|
||
|
```vb
|
||
|
|
||
|
$ASSERTS:CONSOLE
|
||
|
|
||
|
DO
|
||
|
a = INT(RND * 10)
|
||
|
b$ = myFunc$(a)
|
||
|
PRINT a, , b$
|
||
|
_LIMIT 3
|
||
|
LOOP UNTIL _KEYHIT
|
||
|
|
||
|
FUNCTION myFunc$ (value AS SINGLE)
|
||
|
_ASSERT value > 0, "Value cannot be zero"
|
||
|
_ASSERT value <= 10, "Value cannot exceed 10"
|
||
|
|
||
|
IF value > 1 THEN plural$ = "s"
|
||
|
myFunc$ = STRING$(value, "*") + STR$(value) + " star" + plural$ + " :-)"
|
||
|
END FUNCTION
|
||
|
|
||
|
```
|
||
|
|
||
|
## See Also
|
||
|
|
||
|
* [$ASSERTS]($ASSERTS)
|
||
|
* [$CHECKING]($CHECKING)
|
||
|
* [Relational Operations](Relational-Operations)
|