CotEditor

CotEditor is a plain text and source code editor for the macOS operating system. It is designed for editing and handling programming files, scripts, and technical documentation, integrating specific tools for these tasks.

★★★★★

5.0(1 ratings)

• Syntax highlighting. It colors code in more than 50 pre-installed languages, including HTML, PHP, Python, Ruby, JavaScript, C++, and Markdown. The system applies different colors to keywords, text strings, comments, and other syntactic elements. Color schemes are configurable. Users can define rules for additional languages.
• Outline menu. Extracts and displays a list of structures defined in the document, such as functions, classes, or headers, based on syntactic rules. This list allows for quick navigation by clicking on an element. It facilitates orientation in large and complex files.
• Powerful search and replace. Performs search and replace operations using the ICU regular expression engine. Searches can be applied to the current document or multiple open files. It includes options for whole word matching and case sensitivity. Displays results in a list for review.
• Split editor. Allows the main window to be separated into multiple viewing panels. Each panel can display different sections of the same document or different documents. Panels can be arranged horizontally or vertically. Editing is synchronized in real-time.
• Incompatible characters. Identifies and lists characters within the document that cannot be converted to the selected file encoding. This feature prevents encoding errors and data corruption. The tool allows for the selective correction or removal of these characters.
• CJK language support. Includes optimized functions for handling text in Chinese, Japanese, and Korean. It allows switching to vertical writing mode. It correctly manages line height with double-width characters. File encoding estimation for these languages is accurate.
• Scripting and automation. Enables the execution and creation of macros using languages such as Python, Ruby, Perl, PHP, UNIX shell, AppleScript, or JavaScript. Scripts can manipulate text, interact with the editor, and extend its base functionality. They can be assigned to keyboard shortcuts.
• Multiple encodings and line endings. Opens and saves files in a wide range of text encodings, such as UTF-8, UTF-16, Shift JIS, and EUC-JP. On-the-fly encoding conversion. Handles different line ending styles: LF (Unix), CR (classic Mac), and CRLF (Windows), with conversion capability.
• Display of invisible characters. Shows symbols for spaces, tabs, and line breaks. The visibility of these characters is independently configurable. It aids in precise editing of format and alignment in plain text documents and code.
• Information and count panels. Displays detailed document statistics in a sliding panel. Includes character, word, and line counts. Shows information about encoding, line endings, and file metadata when available. The information updates dynamically.
• Plugins. Functionality can be extended through a plugin system. Plugins can add new editing features, integration with external services, or code analysis tools. They are distributed as standalone packages.
• Column multi-editing. Allows for simultaneous text insertion at multiple selection points. It is effective for editing data columns or changing repeated values across different lines. The cursor behaves independently at each selected position.
• Automatic word completion. Suggests words to complete based on the content of the current document. The suggestion list is generated from words already typed in the file. It speeds up the writing of long terms or repetitive variables in programming.
• Indentation detection. Automatically analyzes the indentation style used in a document (tabs or spaces) and its width. When pressing Enter, the new line inherits the indentation from the previous line. Maintains consistency in code formatting without manual intervention.
• Column guide. Displays a vertical line at a specific column in the editor, typically at column 80 or 120. It serves as a visual reference to keep line width within defined limits. The guide's position is user-configurable.

CotEditor was created by the Japanese developer 1024jp. Development began in the year 2014. The program is written primarily in the Swift programming language, with some components in Objective-C.

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