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GrapaPy Namespace Solution

Problem Solved

The original issue was that GrapaPy file and table operations were returning {"error":-1} when using the $file() object. This was caused by a fundamental misunderstanding of how GrapaPy handles namespaces.

Root Cause

GrapaPy has two execution modes that affect variable persistence:

Direct Execution (No Parameters)

  • Execution level: Global namespace
  • Variable persistence: Variables persist automatically between calls
  • $global usage: Not needed for variable persistence

Parameterized Execution (With Parameters)

  • Execution level: Local scope on top of global
  • Variable persistence: Variables are local and don't persist between calls
  • $global usage: Required for variable persistence

When we created a $file() object without understanding the execution model, it was being created in the wrong scope and deleted before we could use it in subsequent calls.

Solution

The solution depends on your execution mode:

Direct Execution (No Parameters) - Simple Approach

import grapapy

xy = grapapy.grapa()

# Variables persist automatically - no $global needed
xy.eval("fs = $file();")
xy.eval("fs.set('test.txt', 'Hello World');")
content = xy.eval("fs.get('test.txt');")
print(content)  # Hello World

Parameterized Execution (With Parameters) - Use $global

import grapapy

xy = grapapy.grapa()

# When using parameters, use $global for persistence
xy.eval("$global.fs = $file();", {'x': 5})
xy.eval("fs.set('test.txt', 'Hello World');")
content = xy.eval("fs.get('test.txt');")
print(content)  # Hello World

import grapapy

xy = grapapy.grapa()

# Initialize persistent objects with $global (works in both modes)
xy.eval("$global.fs = $file();")

# Use objects directly (Grapa finds them in global namespace)
xy.eval("fs.set('test.txt', 'Hello World');")
content = xy.eval("fs.get('test.txt');")
print(content)  # Hello World

Variable Resolution Order

Grapa searches for variables in this order: 1. Current context (within { } brackets) 2. Function scope 3. Local namespace 4. Call stack namespaces 5. Global namespace

Key Insights

  1. Execution mode determines persistence - Direct execution persists variables automatically, parameterized execution requires $global
  2. The $ character is NOT the problem - It works correctly in GrapaPy
  3. Namespace management is the key - Use global namespace for persistent objects when using parameters
  4. Mixed approach is recommended - Use $global for initialization to work in both modes
  5. All Grapa operations work - File system, database, grep, etc.

Test Results

Our comprehensive test shows that with the global namespace approach:

  • ✅ File operations work perfectly
  • ✅ Table operations work perfectly
  • ✅ Directory operations work perfectly
  • ✅ File splitting works perfectly
  • ✅ Performance operations work perfectly
  • ✅ Error handling works correctly

Best Practices

  1. Initialize objects in global namespace: $global.fs = $file();
  2. Use simple variable names: fs.set() instead of $global.fs.set()
  3. Handle binary data properly: Check for bytes and decode if needed
  4. Use batch operations: Leverage Grapa's built-in loops for performance

Conclusion

The GrapaPy extension works perfectly for all Grapa operations when using the correct namespace management approach. The original {"error":-1} issues were entirely due to namespace scope, not fundamental problems with the extension.

This solution enables full Python integration with Grapa's powerful file system, database, and grep capabilities.