Thank you. It's not the behavior of map or grep that was/is mysterious to me, but the particular use of "\e[${_}m", which looks like some manner of regex (which it isn't), and I couldn't figure out what it was supposed to be doing to the numbers. I got hung up on the presence of an open square bracket but no closing square bracket, and the ${_} which looks like some sort of default variable distinct from $_, but for which I could find no definition. If I understand right from afoken's comment, then ${_} substitutes in the values from the provided list, which is what I would have expected $_ to do in a map. Is there anywhere the ${_} form is documented so I could read up on it? I had read the various docs you pointed to and didn't find it there. If it is not a form of its own, why use the curly braces instead of just $_?

In reply to Re^13: Immediately writing the results of search-and-replace by elemkeh
in thread Immediately writing the results of search-and-replace by Anonymous Monk

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