RDC00101 — Implicit declarations enabled

Severity: Warning · Family: RDC (Rubberduck Core analyzers) · Raised by: OptionExplicitAnalyzer

A module does not state Option Explicit.

Without it, a name that is not declared is not an error: a variable comes into being where it is used (MS-VBAL §5.2.1.3 Option Explicit Directive), so a misspelled name goes unnoticed and the program runs with a variable that nothing ever assigns. The diagnostic is an opinion of the analyzer and not a condition of the language: both are legal VBA.

Whether the module states Option Explicit is a fact the environment host vouches for (ModuleSemanticModel.OptionExplicit); the analyzer has nothing to say about a module the host has not analyzed, and does not guess from the syntax tree.

The fact is not issued for a language that has no such directive (SupportedLanguage.HasOptionExplicit): a BASIC, which an interactive shell is written in, has no way to state it, so a module of it is never reported as not stating it. VBA and VB6 have it.

How it is raised

Situation	Resolution
The module has no `Option Explicit` directive.	Add `Option Explicit` at the top of the module, and declare what it then reports.

Table of Contents

RDC00101 — Implicit declarations enabled

How it is raised

See also