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Overview

The NameGenerator class generates unique, sequential obfuscated identifiers in the format _$0, _$1, _$2, etc. It’s used by the RenamePass to create meaningless replacement names for classes, methods, and fields. Source: lib/src/engine/name_generator.dart:2

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Constructor

NameGenerator({String prefix = r'_$'})
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prefix
String
default:"_$"
The prefix for generated names. Defaults to _$.

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Methods

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next()

String next()
Returns the next unique obfuscated name by incrementing an internal counter.
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return
String
The next sequential name, e.g., _$0, _$1, _$2, etc.
Example: 
final gen = NameGenerator();
print(gen.next()); // _$0
print(gen.next()); // _$1
print(gen.next()); // _$2

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reset()

void reset()
Resets the internal counter to 0. Useful for testing or when starting a new obfuscation run. Example: 
final gen = NameGenerator();
gen.next(); // _$0
gen.next(); // _$1
gen.reset();
gen.next(); // _$0 (counter restarted)

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Properties

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currentCount

int get currentCount
Returns the current counter value without incrementing it. Useful for debugging or reporting.
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currentCount
int
The current counter value (number of names generated since last reset)
Example: 
final gen = NameGenerator();
gen.next();
gen.next();
print(gen.currentCount); // 2

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Custom Prefixes

You can customize the prefix to match your obfuscation needs: 
// Generate names like o0, o1, o2...
final gen = NameGenerator(prefix: 'o');

// Generate names like a_0, a_1, a_2...
final gen2 = NameGenerator(prefix: 'a_');
The default prefix _$ is chosen because:
  • Identifiers starting with underscore are private in Dart (library-scoped)
  • The $ character is valid in identifiers but uncommon in user code
  • Together they create names unlikely to collide with existing code

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Usage with PassContext

NameGenerator is typically accessed through PassContext: 
class MyCustomPass extends Pass {
  @override
  String get name => 'my_pass';

  @override
  void run(Component component, PassContext context) {
    final nameGen = context.nameGenerator;
    
    // Generate obfuscated names
    final className = nameGen.next();
    final methodName = nameGen.next();
    
    print('Class: $className');  // _$0
    print('Method: $methodName'); // _$1
  }
}

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See Also

RenamePass

Uses NameGenerator to create obfuscated identifiers

PassContext

Provides access to the shared NameGenerator instance

SymbolTable

Records mappings from original to generated names

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