dart-multiline-strings

Dart Multi-line Strings

1. When to use this skill

Use this skill when:

• Refactoring consecutive print() or stdout.writeln() statements into a single, cohesive output block.
• Simplifying string literals that span multiple lines, contain embedded newlines (\n), or use nested indentations.
• Formatting large user-facing text output (like CLI help menus, reports, or templated messages) to be readable, maintainable, and performant.

Discovery

To find candidate code blocks for multi-line string refactoring:

• Look for multiple back-to-back print() or stdout.writeln() calls inside a function, especially inside loops, console views, or CLI controllers.
• Look for single-line strings heavily loaded with \n escape sequences.
• Look for multiple string concatenations using the + operator or adjacent string literal splits that are meant to represent multi-line outputs.

2. Guidelines

Combine Consecutive Outputs

Instead of calling print() repeatedly for a multi-line output, group the contents into a single triple-quoted string literal: print('''...''').

Explicit and Clean Alignment

In a triple-quoted literal, the exact spacing and formatting inside the quotes are preserved. Use this to specify indentation levels visually instead of using manually padded space prefixes (e.g., ' ').

Remove Empty Print Calls

If there are empty print() or print('') statements serving as vertical separators between output segments, replace them by letting the trailing newline of a multi-line string block handle the separation naturally.

Handling the First Newline

If the opening triple-quote is immediately followed by a newline, the compiler discards it.

• If you do not want a leading blank line, start the string content on a fresh line in the source code for clean layout.
• If you do want a leading blank line in the output, leave an extra empty line inside the triple-quoted block, or use \n explicitly at the beginning:

  print('''
  
  This starts with one blank line above it.''');