+
−-*- mode: outline -*-
+
−
+
−* How debug ini file?
+
−
+
−When your InitFile has a bug, or when you load external files that cause
+
−errors, the bug is often hard to find, because the Emacs Lisp reader does not
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−know about line numbers and files – it just knows an error happened, and
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−that’s it.
+
−
+
−** Binary Search.
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−
+
−Select half of the file in a region, and M-x eval-region. Depending on whether
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−that causes the error or not, split this half or the other half again, and
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−repeat.
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−
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−** Elisp.
+
−
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− - Use a keyboard macro that moves forward one expression (sexp) and evaluates
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−   it.
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− - Try C-x check-parens.
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− - Set (setq debug-on-error t).
+
−
+
−** CLI.
+
−
+
−  $ emacs --no-init-file --no-site-file --debug-init
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−
+
−** Simplified Binary Search.
+
−
+
−Add (error “No error until here”) in the middle of your file. If you get the
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−error “No error until here” when reloading the file, move the expression
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−towards the back of the file, otherwise towards the front of the file.
+
−
+
−* Using edebug.
+
−
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−The main entry point is ‘M-x edebug-defun’ (also on ‘C-u C-M-x’). Use it
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−instead of `C-x C-e’ or ‘C-M-x’ to evaluate a ‘defun’ and instrument it for
+
−debugging.
+
−
+
−You can disable edebug on a function by evaluating the function again using
+
−‘C-M-x’.
+
−
+
−* How debug func?
+
−
+
−Use M-x debug-on-entry and M-x cancel-debug-on-entry to control
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−which functions will enter the debugger when called.
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−
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−When next time that function called automatically loaded debug-mode.