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-rw-r--r--ship/README.markdown22
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Undo `make install` with
make distclean
+
+## Macro Development
+
+ To define a new macro, you have to add a function like
+
+ ## usage: BRE -> FUNCTION_NAME \1 [\2 ...]
+
+ where `BRE` is a basic regular expression, that has to match a whole
+ line. `FUNCTION_NAME` should be the name of a function that outputs
+ a `sed` script. `\1` refers to the line number, where the macro is
+ used and `\2 ...` are the backreferences into `BRE`. E.g.
+
+ ## usage: #@date \([.*]\) -> build_datemacro \1 \2
+ build_datemacro() {
+ printf '%da\\\n%s\n' "$1" "$(date +"$2")"
+ }
+
+ Like in this example, the line number `\1`, which gets mapped to `$1`,
+ is usually used to only change the line, where the macro got called.
+ The second argument gets passed as format specifier to `date`.
+
+ Further examples can be found in `./build`.