Table of Contents

3.4.1 Block Statements

A block statement holds nested statements. The block statements belong to MS-VBAL §5.4.2 Control Statements; each is cross-referenced below to its MS-VBAL section and to the RD-VBAL page that describes its implementation.

Statement Node type(s) MS-VBAL RD-VBAL
If...Then...ElseIf...Else...End If IfBlockStatementNode, ElseIfBlockStatementNode, ElseBlockStatementNode MS-VBAL §5.4.2.8 If Statement RD-VBAL §5.4.2.8 If Statement
While...Wend WhileWendStatementNode MS-VBAL §5.4.2.2 While Statement RD-VBAL §5.4.2.2 While Statement
For...Next ForStatementNode MS-VBAL §5.4.2.3 For Statement RD-VBAL §5.4.2.3 For Statement
For Each...Next ForEachStatementNode MS-VBAL §5.4.2.4 For Each Statement RD-VBAL §5.4.2.4 For Each Statement
Do...Loop (five header shapes; see Do Loop Forms) DoLoopStatementNode, DoWhileLoopStatementNode, DoUntilLoopStatementNode, DoLoopWhileStatementNode, DoLoopUntilStatementNode MS-VBAL §5.4.2.6 Do Statement RD-VBAL §5.4.2.6 Do Statement
Select Case...End Select SelectCaseStatementNode, CaseExpressionStatementNode, CaseElseClauseStatementNode MS-VBAL §5.4.2.10 Select Case Statement RD-VBAL §5.4.2.10 Select Case Statement
With...End With WithStatementNode MS-VBAL §5.4.2.21 With Statement RD-VBAL §5.4.2.21 With Statement
Single-line If...Then...Else InlineIfStatementNode; see Single-line If MS-VBAL §5.4.2.9 Single-line If Statement RD-VBAL §5.4.2.9 Single-line If Statement

Node Shape

Every block statement node follows the same shape:

  • its header condition(s) and expression(s) are named properties of the node;
  • its nested statements are held in a Body property of type StatementBlock.

The uniform Body: StatementBlock shape is deliberate. It keeps the whole block-statement family (the block statements of MS-VBAL §5.4.2) consistent, rather than giving each node an undifferentiated list of children.

Three nodes hold their nested statements differently:

Node Nested statements
InlineIfStatementNode One StatementBlock per branch: ThenBody and ElseBody.
CaseExpressionStatementNode A StatementBlock named Block.
SelectCaseStatementNode No StatementBlock of its own: it holds its Case and Case Else nodes, and each of those holds one.

A block statement's StatementBlock is independent of the statement node's Inputs; see RD-VBAL §3.4.0 Statements.

Following MS-VBAL, Next, Loop and Wend have no AST node of their own. The whole construct is one node (ForStatementNode, DoLoopStatementNode, and so on) with a Body; see RD-VBAL §3.5.3 Lowering Block Statements.

Do Loop Forms

Do...Loop has five header shapes, each represented by its own node type (MS-VBAL §5.4.2.6):

Header shape Node type
Do ... Loop DoLoopStatementNode
Do While ... Loop DoWhileLoopStatementNode
Do Until ... Loop DoUntilLoopStatementNode
Do ... Loop While DoLoopWhileStatementNode
Do ... Loop Until DoLoopUntilStatementNode

Single-line If

InlineIfStatementNode's ThenBody and ElseBody may each hold several colon-separated statements instead of a full block (MS-VBAL §5.4.2.9).

Tip

A bare line-number target in either branch (If x Then 100) is not modelled as its own AST shape. MS-VBAL specifies such a target as equivalent to a GoTo statement targeting that line. The parser therefore synthesizes a GoToStatementNode as that branch's statement, typically its only one.

Case Clauses

Each Case line's comma-separated conditions form their own node hierarchy under the abstract CaseRangeClauseNode. The three condition forms of MS-VBAL §5.4.2.10 are modelled independently, as three node types:

Condition form Example Node type
Single value Case 5 CaseValueRangeClauseNode
Comparison Case Is > 5 CaseComparisonRangeClauseNode
Inclusive range Case 1 To 10 CaseToRangeClauseNode

⏮️ RD-VBAL §3.4.0 Statements | ⏭️ RD-VBAL §3.4.2 Simple Statements

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