Named captures in Ruby - Mini Project: Build & Apply

Extracting Date Components with Named Captures in Ruby

📖 Scenario: Imagine you have a list of dates in the format YYYY-MM-DD. You want to pull out the year, month, and day parts separately to use them later, like sorting or filtering.

🎯 Goal: Build a Ruby program that uses a regular expression with named captures to extract the year, month, and day from a date string.

📋 What You'll Learn

Create a string variable called date with the value "2024-06-15".

Create a regular expression called date_regex that uses named captures for year, month, and day matching the date format.

Use the match method to match date against date_regex and store the result in a variable called match_data.

Print the extracted year, month, and day from match_data using the named captures.

💡 Why This Matters

🌍 Real World

Named captures help you pull out meaningful parts from text like dates, phone numbers, or codes, making it easier to work with data.

💼 Career

Many jobs require processing text data. Knowing how to use named captures in regex helps you write clear and maintainable code for data extraction.

1

Create the date string

Create a string variable called date and set it to "2024-06-15".

Ruby

# Create the date string
# Your code here

Need a hint?

Use = to assign the string to the variable date.

2

Create the named capture regex

Create a regular expression variable called date_regex that matches the format YYYY-MM-DD using named captures for year, month, and day. Use the syntax /(?\d{4})-(?\d{2})-(?\d{2})/.

Ruby

date = "2024-06-15"
# Create the named capture regex
# Your code here

Need a hint?

Use /.../ to create the regex and ? for named captures.

3

Match the date string with the regex

Use the match method to match date against date_regex and assign the result to a variable called match_data. Use match_data = date_regex.match(date).

Ruby

date = "2024-06-15"
date_regex = /(?\d{4})-(?\d{2})-(?\d{2})/
# Match the date string with the regex
# Your code here

Need a hint?

Use the match method on the regex to get the match data.

4

Print the extracted year, month, and day

Print the year, month, and day from match_data using the named captures. Use puts match_data[:year], puts match_data[:month], and puts match_data[:day].

Ruby

date = "2024-06-15"
date_regex = /(?\d{4})-(?\d{2})-(?\d{2})/
match_data = date_regex.match(date)
# Print the year, month, and day
# Your code here

Need a hint?

Use puts to print each part on its own line.