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🔍 Understanding the $syntax Function in Uniface 10.4

Note: This blog post was created with the assistance of AI technology.

If you work with Uniface 10.4, you might have come across the $syntax function. This powerful tool helps you match text patterns in your applications. Let me show you how it works in simple terms! 💡

📝 What Does $syntax Do?

The $syntax function converts a regular string into a special pattern string. Think of it like creating a template that other strings can match against. This is super useful when you need to check if user input follows a specific format.

Basic Structure 

$syntax(String, SyntaxMode)
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  • String: The text you want to convert
  • SyntaxMode: How the matching should work (optional)

🎯 Syntax Modes Explained

Uniface offers four different modes to control how pattern matching works:

1. Classic Mode (Default) 🔧

This mode treats special characters like #, *, &, @ as pattern codes.

$syntax("D&G")
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This creates the pattern '%[X]D&G' which matches DOG, DIG, DUG, etc. The & acts as a wildcard for any single character!

2. CaseSensitive Mode 🔠

Perfect when exact case matters! Special characters are treated as normal text.

$syntax("D&G", "CS")
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This only matches the exact string "D&G" with the same uppercase letters.

3. CaseInsensitive Mode 🔡

Ignores uppercase and lowercase differences. Great for user-friendly searches!

$syntax("D&G", "CI")
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This matches D&G, d&g, D&g, or any combination of upper and lowercase.

4. NlsLocale Mode 🌍

Handles special characters from different languages according to locale settings.

$syntax("i#B", "NlsLocale")
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In Turkish locale, this correctly handles the dotted and dotless "i" characters!

💼 Real-World Example

Imagine you need to check if a customer name matches a pattern:

if (NAME1 = $syntax("D&G", "CaseInsensitive"))
    ; Name matches the pattern
    message "Name matches!"
else
    ; Name doesn't match
    message "Name doesn't match."
endif
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This checks if the NAME1 field contains text matching the pattern, ignoring case differences.

⚠️ Important Things to Remember

  • The pattern must appear within the first 256 characters of the string you're checking
  • If something goes wrong, $syntax returns an empty string
  • Check $procerror for error details (value -1013 means invalid syntax string)
  • You can use this function in all Uniface component types

🎓 When Should You Use $syntax?

Here are some practical scenarios:

  • Form Validation: Check if user input matches required formats
  • Search Features: Create flexible search that ignores case
  • Data Filtering: Find records matching specific patterns
  • International Apps: Handle text with special characters correctly

🚀 Pro Tips

  1. Start Simple: Use "Classic" mode first to understand pattern codes
  2. Test Thoroughly: Different modes behave very differently
  3. Handle Errors: Always check $procerror after using $syntax
  4. Choose the Right Mode: Match the mode to your business requirements

✨ Conclusion

The $syntax function is a powerful tool in your Uniface toolkit. Whether you need exact matching, case-insensitive searches, or international character support, there's a mode for your needs. Start experimenting with simple patterns and gradually work your way up to more complex scenarios! 🎉

Happy coding! 👨‍💻👩‍💻

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