Low

// Generated Code Library declaration:
function Low: Int64;

// Effective call contract:
function Low(X): Int64;

Example

procedure ScriptEvent(var Value: variant);
begin
  Value := Low('Velox'); // 1
end;

Usage

Parameters

Name	Type	Description
X	supported value	Dynamic/static array, string or supported integer value whose value type/range is inspected.

Pass a value or variable. A bare type identifier is not part of the verified external-call contract.

Returns

Runtime argument type	Result
Dynamic array	0, including an empty array
Static array	its declared start offset
String	1, including an empty string
Byte, Word, Cardinal, UInt64	0
ShortInt	-128
SmallInt	-32768
Integer	-2147483648
Int64	-9223372036854775808

Additional Technical Info

Low returns the lower index of a supported array/string value or the minimum value for a supported integer storage type.

The generated declaration is incomplete: the compiler adds a required untyped argument named X after creating the displayed declaration. This external runtime helper is narrower than Delphi's compiler intrinsic. The example is fictional and source-reviewed only.

Implementation

1. The compiler adds the synthetic input parameter.
2. Runtime Low_ resolves the parameter's PascalScript type.
3. Arrays/strings return hard-coded/index metadata; integer branches return host type constants.
4. The result is written to the declared Int64 return slot.
5. Unsupported types return failure and become a script call/type error.

Edge cases and differences from Delphi

• An empty dynamic array has Low=0 and High=-1; an empty string has Low=1 and High=0. A loop guarded only by Low is therefore unsafe for empties.
• Characters, enumerations, sets, Variants, objects and pointers are not supported branches. Low does not return an enumeration's first declared member.
• The value of a numeric argument is ignored; only its base type matters.
• Delphi's intrinsic supports more type-identifier and ordinal forms and can return the argument/index type. Velox fixes the return to Int64.
• Static arrays can have a non-zero or negative declared start offset; the runtime preserves that offset.

Side effects

The function does not mutate X, though the argument expression itself is evaluated normally.

Related entries

• High returns the corresponding upper index/type boundary.
• MinIntValue examines actual elements rather than a type minimum.

External references

• Free Pascal: System.Low
• Embarcadero DocWiki: System.Low

Created 2026-07-15