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MiniRobotLanguage (MRL)

 

BLO.BlockValidate

Checks if all block delimiters are balanced.

 

Intention

 

This command analyzes a string to determine if its delimited blocks are well-formed. It checks that every start delimiter has a corresponding end delimiter and that there are no extra, mismatched end delimiters. This is a crucial diagnostic tool before performing complex parsing operations.

 

                        Validating Block Structure

 

Case 1: Balanced (OK)

[A[B]C]

Level: 1 2  1 0   -> Final Level = 0.  Result: 0

 

Case 2: Unclosed (Error)

[A[B]

Level: 1 2    -> Final Level = 2.  Result: 2

 

Case 3: Mismatched (Error)

[A]]

Level: 1 0 -1 -> Final Level = -1. Result: -1

 

 

 

Syntax

 

BLO.BlockValidate|P1|P2|P3[|P4]

 

Parameter Explanation

 

•P1 - (Input, Text) The source string to validate.

•P2 - (Input, Text) The starting delimiter string.

•P3 - (Input, Text) The ending delimiter string.

•P4 - (Output, Numeric) Optional. Variable to store the numeric result. If omitted, the result is placed on the Top of Stack (TOS).

 

Return Values

 

•0: The string is perfectly balanced.

•Positive Number: Indicates the number of unclosed start delimiters. (e.g., 1 means one block was left open).

•Negative Number: Indicates the number of mismatched end delimiters. (e.g., -1 means one extra closing tag was found).

 

Example

 

'***********************************

' BLO.BlockValidate Example

'***********************************

$$SRC=[A[B]]

BLO.BlockValidate|$$SRC|'['|']'|$$STATUS

' $$STATUS will be 1, because the [A block is not closed.

MBX.Validation Status: $$STATUS

ENR.

 

See also:

 

• BLO.BlockRepair - Repairs strings with unclosed/mismatched blocks