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TvxVariableGroup

TvxVariableGroup = class

Example​

procedure ScriptEvent(var Value: Variant);
begin
  // Replace V_MyGroup with a configured group identifier.
  if V_MyGroup <> nil then
    Value := V_MyGroup.VariableCount
  else
    Value := 0;
end;

Usage​

TvxVariableGroup represents a Velox-provided cached global variable group exposed to scripts under its dynamically generated V_ identifier.

Security and concurrency

Variables can contain shared operational values or encrypted-at-rest secrets that are decrypted by their value accessors. Do not log/export values without classification and authorisation. Avoid read-modify-write sequences that assume isolation; another execution can change a variable between calls.

Additional Technical Info​

TvxVariableGroup is a configured module containing process-global TvxVariable objects. Velox caches groups and makes each one available to scripts under a generated global identifier.

Acquisition and naming

There is no fixed VariableGroup variable and no script constructor. A non-default group identifier is formed as:

V_ + ModuleName with spaces removed

For example, a module named My Group is registered as V_MyGroup. The default group uses V_Variables. Pascal identifiers are case-insensitive, but setup must still produce a valid, unique identifier; punctuation and other invalid characters are not removed by this naming step.

Velox registers/binds every cached group while preparing a scripter. A group that is missing from the cache at that time is not a declared identifier for that compiled script.

Script-visible members

  • VariableByCode performs a case-insensitive lookup and is the default indexed property.
  • VariableCount returns the current child count.
  • Variables returns a child by zero-based index.

All returned variables are live host-owned objects, not copies. Their values can be shared by unrelated actions/threads. A direct variable-value assignment changes cached runtime state but does not itself invoke the group module's SaveModule operation.

Cache and lifetime

Groups load from configuration into a process-global cache. Saving/deleting a group, switching mode or explicitly clearing the cache can remove and free a cached object, then load a replacement. Never free a group/variable or retain its reference outside current use.

Each accessor locks the group only while locating/counting a child. The lock has ended when it returns the object. A count followed by an index access is not one atomic operation, and host structural changes/cache replacement can invalidate assumptions or references.

Tag access

Variable-group tags use:

<*GroupName.VariableCode*>

Tag processing adds V_ internally, loads/resolves the group and variable, and replaces all case-insensitive tag occurrences with the variable's AsString. A missing group or variable raises an exception. Script indexed access instead returns nil for a missing code.

Created 2026-07-15