Migration Guide: isValid() / validate() Deprecation

Texpr.isValid() and Texpr.validate() are deprecated and will be removed in 1.0.0.

Use parse() with try/catch instead.

Why this change?

• Single parsing entry point reduces API surface.
• Parse exceptions already provide structured diagnostics (message, position, suggestion).
• Encourages a single error-handling model across parsing and evaluation.

Migration Patterns

1) Replace isValid()

Before:

final ok = texpr.isValid(input);
if (!ok) {
  return;
}

After:

try {
  texpr.parse(input);
  // valid
} on TexprException {
  // invalid
}

2) Replace validate() with rich error handling

Before:

final result = texpr.validate(input);
if (!result.isValid) {
  print(result.errorMessage);
  print(result.position);
  print(result.suggestion);
}

After:

try {
  texpr.parse(input);
} on TexprException catch (e) {
  print(e.message);
  print(e.position);
  print(e.suggestion);
}

3) Keep parse result for reuse

Expression ast;
try {
  ast = texpr.parse(input);
} on TexprException catch (e) {
  // report validation-style diagnostics
  rethrow;
}

final value = texpr.evaluateParsed(ast, {'x': 2.0});

Timeline

• Now (0.1.x): methods are available but deprecated.
• 1.0.0: methods are removed.