ExamDiff Pro tutorial · Source code
How to Compare Source Code on Windows
Compare two versions of a source file with full syntax highlighting, see which function you are in and which functions changed, and let ExamDiff Pro match functions and classes by their signatures, so the diff lines up the right code. The language is recognized even for code without a file extension and for code you paste in.
Video
Steps
- Compare the two files: choose Files | New Comparison (Ctrl+E), select Compare Files, pick the files, and click Compare. ExamDiff Pro recognizes the language from the file extension and highlights the syntax in both panes.
- Click anywhere in a file. The scope bar above each pane shows where you are, for example the class and function. Click a part of the scope bar to list everything at that level: functions that changed between the two files are in bold, and clicking one jumps to it. If the scope bars are hidden, choose View | Scope Bars.
- Matching lines alone can pair the wrong code. In the example, the old file has two versions of
GetNavigatableDiffCount(a short wrapper on line 2 and the real function on line 7), and the new file has one. Line matching pairs the new function with the wrapper. To fix this, choose Tools | Options, go to Text Comparison | Advanced, and turn on Match file structures for comparison.
- Re-compare when asked. ExamDiff Pro now matches functions and classes by their signatures and aligns them, so the new function is paired with the real one on line 7. To see these matches as links, turn on View | Show Synchronizing Splitter and, in the options, Display | Show fuzzy/structure links. Structure links are drawn as orange outlines and fuzzy matching links as magenta outlines; links you add yourself are filled in green.
- Code without a file extension, or pasted code. Choose Files | New Comparison and click Empty Files. Paste the old version into the left pane and the new version into the right pane. ExamDiff Pro detects the language from the content, highlights the syntax, and shows the language in the status bar below each pane. Re-compare to see what changed. Files without an extension, or with an extension that matches no language, and clipboard comparisons are detected the same way.
Questions
Which languages are supported?
C, C++, C#, Java, JavaScript, TypeScript, Python, Go, Rust, PHP, SQL, XML, HTML, JSON, YAML, and many more. See Document Types in the online help for the full list and to add your own extensions.
The language was detected wrong. Can I choose it?
Yes. Right-click the pane, choose Set Document Type, and pick the language, or choose Auto Detect to detect it again.
Can I turn language detection off?
Yes. Choose Tools | Options, go to Document Types, and clear Automatically detect document type for unknown extensions. It is on by default.
When should I turn on structure matching?
When functions or classes were added, removed, renamed, or overloaded and the comparison pairs the wrong ones. In most comparisons, matching by line content already lines up the right code.
Can I ignore comments or white space when comparing code?
Yes, with the Ignore Comments, Ignore White Space, and Ignore Blank Lines toolbar buttons, or in Tools | Options.
Can I use this with Git?
Yes. See How to Use ExamDiff Pro with Git.