2.6.1 Syntax Errors

A syntax error is raised while the parser traverses the concrete syntax tree (CST). It is a token the grammar cannot place.


Code family	`VBC`, range `VBC00001`–`VBC00999`
Title	Syntax error
Raised by	the parser (concrete syntax tree)
Source metadata	VBSyntaxErrorInfo; its `ErrorId` is a VBCompileErrorId
Severity	`Error`
Detail	the faulted token and its expected role, on `Diagnostic.data`

Syntax and Semantic Compilation Errors

MS-VBAL does not distinguish a compile-time error raised in CST semantics from one raised in AST semantics. RDCore splits CST-semantics (syntax) errors and AST-semantics (semantic compilation) errors by numeric range only.

Every VBCompileErrorId value below 9300 belongs to the parser; [9300..] is reserved for semantic compilation errors. Errors issued from the parser are normally syntax errors with a VBCompileErrorId value between 42 and 999; see RD-VBAL §1.1.4 Core Diagnostics.

Conditions that need symbol information (an undefined name, a duplicate declaration) are not syntax errors. They are reported later, as semantic compilation errors.

Fallback and Dedicated Codes

VBC00001 is the general syntax-error fallback code: when the input is invalid and no more specific code applies, the parser reports VBC00001.

The parser narrows its output: recurring syntax-error shapes are promoted to a dedicated code in the VBC00042–VBC00999 range.

A numeric literal whose value does not fit its type is the NumericLiteralOverflow syntax error (VBC00042), located at the literal. This includes a literal whose value does not fit its suffix-forced type, a floating-point literal that overflows to infinity, and an unsuffixed radix literal beyond 32 bits; see RD-VBAL §3.2.0 Literal Expressions.

A procedure whose blocks do not match - a Next with no For, a block If with no End If, and so on - is the syntax error MS-VBA names for it (VBC00043–VBC00053), at the statement that does not fit, rather than what the grammar expected where it could no longer parse.

An argument list that ends with an omitted argument - Total(1, ), Report 1, - is a syntax error (VBC00001), at the omitted argument, for an Optional parameter too: MS-VBAL §5.6.13.1 makes the last positional argument of a list a required one, and MS-VBA refuses it (recorded in Excel). The RD-VBA grammar reads the list, and the declaration pass refuses it. An omitted argument before another is valid (Total(1, , 3)), and so is a list of no argument at all (Total()).

Conditional Compilation

A directive is a logical line (MS-VBAL §3.2.2, §3.4): the physical lines a line-continuation joins to a line that starts with # are the directive's, and are no code of the module. #Const Debugging = _ followed by 1 is one #Const, and so is a #If or a #ElseIf, or a comment after a directive, that continues over lines, and the # of a directive may stand apart from its keyword (# If, # _ followed by If 1 Then). A line that starts with # and continues another line is not a directive: d = _ followed by #1/2/2000# assigns a date literal. MS-VBA reads them so (recorded in Excel).

Note

Not implemented. A #If that splits a single statement across conditional-compilation branches (#If / #Else / #End If) is unparseable by the RD-VBA grammar. Such a statement reports located VBC diagnostics (VBC00001), which a client can anchor to a source range.

Published Codes

Code	Title	Condition
`VBC00001`	Syntax error	a token the grammar cannot place
`VBC00042`	Numeric literal overflow	a numeric literal outside the range of its type
`VBC00043`	Next without For	a `Next` statement ends no `For` loop
`VBC00044`	For without Next	a `For` loop is not ended before its procedure is
`VBC00045`	Loop without Do	a `Loop` statement ends no `Do` loop
`VBC00046`	Do without Loop	a `Do` loop is not ended before its procedure is
`VBC00047`	End If without block If	an `End If` statement ends no block `If`
`VBC00048`	Block If without End If	a block `If` is not ended before its procedure is
`VBC00049`	Else without If	an `Else` statement belongs to no block `If`
`VBC00050`	Case without Select Case	a `Case` clause belongs to no `Select Case` statement
`VBC00051`	Select Case without End Select	a `Select Case` statement is not ended before its procedure is
`VBC00052`	End With without With	an `End With` statement ends no `With` block
`VBC00053`	Expected End With	a `With` block is not ended before its procedure is
`VBC00054`	Invalid outside procedure	a statement that runs is written in the declarations section of a module
`VBC00055`	Only comments may appear after End Sub, End Function, or End Property	a declaration or a statement is written after the first procedure of a module