Enhance error handling and documentation in PL/SQL splitter

- Improved error reporting by adding context lines around syntax errors, allowing users to see surrounding code for better debugging.
- Updated README.md to include new features and usage examples for enhanced error handling.
- Introduced a new funding configuration file for project support.
- Adjusted command-line flags to support context line configuration for error reporting.
- Enhanced tests to validate the new error context functionality and ensure accurate error messages.
- Updated parser grammar to support additional PL/SQL constructs, including declare blocks.

Author: Jaco Labuschagne

.github/FUNDING.yml

@@ -0,0 +1 @@
+ko_fi: zodimo 

README.md

@@ -3,7 +3,9 @@
 A Go library for accurately splitting Oracle PL/SQL scripts into individual statements with precise boundary detection using ANTLR4 for parsing.
 
 # DISCLAIMER
-This project was created with the help of an ai coding assistent.
+This project was created with the help of AI assistance:
+- Development performed using [Cursor IDE](https://cursor.com), an AI-powered code editor
+- Project structure and development methodology based on the [VAN Memory Bank](https://github.com/vanzan01/cursor-memory-bank) framework
 
 ## Overview
 
@@ -324,4 +326,69 @@ Planned enhancements for future releases:
 - Streaming support for processing very large files
 - Enhanced error recovery for incomplete statements
 - Support for additional Oracle-specific syntax
-- Performance optimizations for large scripts
+- Performance optimizations for large scripts
+
+### Advanced Error Handling
+
+The library provides detailed error reporting capabilities to help diagnose and fix syntax errors:
+
+```go
+package main
+
+import (
+    "fmt"
+    "log"
+    
+    "github.com/zodimo/go-plsql-statement-splitter/pkg/splitter"
+)
+
+func main() {
+    // Create a splitter with enhanced error reporting
+    s := splitter.NewSplitter(
+        splitter.WithVerboseErrors(true),         // Include detailed error messages
+        splitter.WithMaxErrors(5),                // Maximum number of errors to report
+        splitter.WithErrorContext(true),          // Include error context
+        splitter.WithErrorContextLines(5),        // Show 5 lines before and after each error
+        splitter.WithErrorStatement(true),        // Include statement causing error
+    )
+    
+    // Try to split statements and handle errors
+    _, err := s.SplitFile("path/to/script.sql")
+    if err != nil {
+        syntaxErr, isSyntaxErr := err.(*splitter.SyntaxError)
+        if isSyntaxErr {
+            // This will print the error with context showing 5 lines before and after
+            fmt.Printf("Syntax error detected:\n%s\n", syntaxErr.Error())
+        } else {
+            log.Fatalf("Error: %v", err)
+        }
+    }
+}
+```
+
+An example of the enhanced error output:
+
+```
+Syntax error at line 42, column 10: mismatched input 'END' expecting {';', ','}
+40 |     FOR emp IN (SELECT * FROM employees) LOOP
+41 |         DBMS_OUTPUT.PUT_LINE('Employee: ' || emp.name)
+42 |     END LOOP
+           ^
+43 | END;
+44 | /
+```
+
+The error output includes:
+- Error message with line and column number
+- Context showing several lines before and after the error
+- A marker (^) pointing precisely to the error position
+
+## Acknowledgements
+
+### Development Tools
+
+- [Cursor](https://cursor.com) - An advanced IDE powered by AI that was used for the development of this project.
+
+### Development Methodology
+
+This project utilizes the structured memory bank system developed by [vanzan01 - cursor-memory-bank](https://github.com/vanzan01/cursor-memory-bank), which provides an organized framework for AI-assisted software development.

cmd/splitter/main.go

@@ -26,6 +26,7 @@ func main() {
 		allErrors           bool
 		jsonPretty          bool
 		jsonIndent          string
+		contextLines        int
 	)
 
 	flag.StringVar(&outputFormat, "format", "text", "Output format: text or json")
@@ -40,6 +41,7 @@ func main() {
 	flag.BoolVar(&allErrors, "all-errors", false, "Show all errors, ignoring max-errors setting")
 	flag.BoolVar(&jsonPretty, "pretty", true, "Pretty print JSON output")
 	flag.StringVar(&jsonIndent, "indent", "  ", "Indentation for JSON output")
+	flag.IntVar(&contextLines, "context-lines", 3, "Number of context lines to show before and after errors")
 	flag.Parse()
 
 	// Check if a file path was provided
@@ -55,7 +57,7 @@ func main() {
 		fmt.Println("  splitter -format=json script.sql")
 		fmt.Println("  splitter -format=json -output=result.json script.sql")
 		fmt.Println("  splitter -verbose-errors script.sql")
-		fmt.Println("  splitter -all-errors -error-context invalid.sql")
+		fmt.Println("  splitter -all-errors -error-context -context-lines=5 invalid.sql")
 
 		fmt.Println("\nRunning demo...")
 		demoSplitString()
@@ -77,6 +79,7 @@ func main() {
 	}
 	if includeErrorContext {
 		splitterOpts = append(splitterOpts, splitter.WithErrorContext(true))
+		splitterOpts = append(splitterOpts, splitter.WithErrorContextLines(contextLines))
 	}
 	if includeErrorStmt {
 		splitterOpts = append(splitterOpts, splitter.WithErrorStatement(true))
@@ -234,6 +237,7 @@ INSERT INTO employees (id, name) VALUES (1, 'John);
 	s := splitter.NewSplitter(
 		splitter.WithVerboseErrors(true),
 		splitter.WithErrorContext(true),
+		splitter.WithErrorContextLines(5),
 		splitter.WithMaxErrors(5),
 	)
 

internal/parser/PlSqlParser.g4

@@ -5467,7 +5467,7 @@ primary_key_clause
 // Anonymous PL/SQL code block
 
 anonymous_block
-    : (DECLARE seq_of_declare_specs)? BEGIN seq_of_statements (EXCEPTION exception_handler+)? END SEMICOLON
+    : (DECLARE seq_of_declare_specs)? BEGIN seq_of_statements (EXCEPTION exception_handler+)? END (SEMICOLON)?
     ;
 
 // Common DDL Clauses
@@ -5591,7 +5591,11 @@ varray_type_def
 // Statements
 
 seq_of_statements
-    : (statement (';' | EOF) | label_declaration)+
+    : (statement (';' | EOF) | label_declaration | declare_block)+
+    ;
+
+declare_block
+    : DECLARE seq_of_declare_specs? BEGIN seq_of_statements (EXCEPTION exception_handler+)? END (';')?
     ;
 
 label_declaration