build-in functions and values
| name | description | type |
|---|---|---|
| unset | The value to express the lack of thereof. | unset |
| true | bool | |
| false | bool | |
| PLATFORM | The compatibility level of the platform that's currently executing the chartbuild script | CompatibilityLevel |
| PCE | The value of CompatibilityLevel.PCE | CompatibilityLevel |
| RPE | The value of CompatibilityLevel.RPE | CompatibilityLevel |
| PHI | The value of CompatibilityLevel.PHI | CompatibilityLevel |