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Opening parenthesis ('(') expected

Velox reports Opening parenthesis ('(') expected at a small set of explicit compiler grammar points. In the current compiler these are the built-ins Ord, Chr, Succ, Pred and Assigned, an interface ancestor declaration, and arguments for a host-registered attribute.

Example​

procedure ScriptEvent(var Value: Variant);
begin
  Value := Ord 'A'; // Error: Opening parenthesis ('(') expected
end;

Enclose the built-in argument:

Value := Ord('A');

Exact emission families​

ContextRequired shape
Ordinal conversionOrd(Expression)
Character conversionChr(Expression)
Successor/predecessorSucc(Expression) or Pred(Expression)
Assignment testAssigned(Identifier)
PascalScript interfaceinterface(AncestorInterface)
Registered attributeAttributeName(ConstantArguments)

The interface shape is a PascalScript compiler rule. Unlike general Delphi syntax, this parser path requires an explicit ancestor in parentheses before the GUID brackets.

How Velox detects it​

Each listed parser branch consumes the keyword or registered attribute name and immediately checks for token CSTI_OpenRound. A different next token emits ecOpenRoundExpected before argument or type checking begins.

Ordinary registered function calls use the general call/parameter parser and can report Invalid number of parameters, Comma expected or another expression diagnostic instead. This page should not be treated as a catalogue of every possible missing (.

Correction procedure​

  1. Identify the exact construct immediately before the reported token.
  2. Insert ( after the built-in, interface keyword or registered attribute name.
  3. Balance it with the corresponding ) and validate the enclosed expression or ancestor.
  4. If this is an ordinary registered routine, inspect its own declaration instead of assuming this diagnostic family applies.

Edge cases and quirks​

  • Assigned reads an identifier-oriented operand in this implementation; a complex calculation can fail after the parenthesis is fixed.
  • Ord, Chr, Succ and Pred perform separate type checks after parsing the opening delimiter.
  • Attribute syntax exists in the compiler, but the standard Velox host currently registers no attribute types, so that emission path is not normally reachable in product scripts.
  • The reported token is the item found instead of (, not necessarily the first malformed token in a larger expression.
  • Closing parenthesis expected - the construct opened correctly but was not closed.
  • Invalid number of parameters - a normal callable has the wrong actual argument count.
  • Class type expected - an interface/class-related expression has the wrong resolved type.

External references​