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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 maintains separate local and global namespaces: - Local namespace: Cleared between calls to xy.eval() - Global namespace: Persists across calls to xy.eval()

When we created a $file() object in the local namespace, it was being deleted before we could use it in subsequent calls.

Solution

Use the global namespace for objects that need to persist across calls:

Correct Pattern

  1. First time (initialization): Use $global.variable to create/initialize the variable
  2. Subsequent times: Use just variable directly - Grapa will find it in the global namespace

Example

import grapapy

xy = grapapy.grapa()

# Initialize file system in global namespace (first time only)
xy.eval("$global.fs = $file();")

# Use file system (no $global needed)
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. The $ character is NOT the problem - It works correctly in GrapaPy
  2. Namespace management is the key - Use global namespace for persistent objects
  3. Only use $global for initialization - After that, just use the variable name
  4. 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.