public IType VisitSubscriptExpression(SubscriptExpression subscriptExpression)
{
var maybeArrayType = GetExpressionType(subscriptExpression.Operand);
if (maybeArrayType is ArrayType arrayType)
{
return(arrayType.UnderlyingType);
}
return(null);
}
public override void Visit(SubscriptExpression exp)
{
exp.AddressExp.AcceptVisitor(this);
foreach (var index in exp.Indices)
{
cb.Write('[');
index.AcceptVisitor(this);
cb.Write(']');
}
}
public virtual void Visit(SubscriptExpression exp)
{
exp.AddressExp.AcceptVisitor(this);
if (exp.Indices != null)
{
foreach (var index in exp.Indices)
{
index.AcceptVisitor(this);
}
}
}
public bool VisitSubscriptExpression(SubscriptExpression subscriptExpression)
{
if (!IsExpressionValid(subscriptExpression.Operand) ||
!IsExpressionValid(subscriptExpression.Index))
{
return(false);
}
var operandType = Typer.GetExpressionType(
_context,
_environment,
subscriptExpression.Operand);
if (operandType == null)
{
return(false);
}
if (!(operandType is ArrayType))
{
_context.Error(
subscriptExpression.Span,
$"cannot index into a non-array type \"{operandType}\"");
return(false);
}
var indexType = Typer.GetExpressionType(
_context,
_environment,
subscriptExpression.Index);
if (indexType == null)
{
return(false);
}
if (!(indexType is IntegerType))
{
_context.Error(
subscriptExpression.Span,
$"type \"{operandType}\" cannot be indexed by type \"{indexType}\"");
return(false);
}
return(true);
}
