Feature suggestion: Insert fields with constant values about xsv HOT 4 OPEN

Seconding the request this insert ability, and expanding on the use case for insert row. Something I currently do occasionally with jq is use it to generate properly-formatted JSON; I would love to be able to do something similar for CSV with the guarantee of all the quoting and escaping.

For example, with jq, I might do:

JSON_TEMPLATE='{$filePath, $size, $mtime}'
JSON=$(
    jq -n -c\
    --arg 'filePath' "$PATH" \
    --arg 'size' "${SIZE}" \
    --arg 'mtime' "${MTIME}" \
    "$JSON_TEMPLATE"
  )

to generate a line like {"filePath": "...", "size": "...", "mtime": "..."}

Going off of the syntax suggested by the OP, this could be something like:

xsv insert row filePath:"$PATH" size:"$SIZE" mtime:"$MTIME" > file.csv

or even something lower-level, like

xsv format "$PATH" "$SIZE" "$MTIME" >> file.csv

to allow for specifying various options (delimiter, line endings, column types, etc).

I'd be okay hearing that this is out of scope for this project, but it feels like it would be nice to have in a CLI "toolkit"

from xsv.

Not as convenient and requires an extra file, but this is already possible with a cross join:

cat > table.csv <<EOF
a,b
1,2
2,4
EOF

# file for fixed column
cat > fixed.csv << EOF
c
FIXED
EOF

# add the column to table.csv
xsv join --cross 1 table.csv 1 fixed.csv

This results in the following output:

a,b,c
1,2,FIXED
2,4,FIXED

from xsv.

I can see how this might be occasionally useful.

from xsv.

I need this today

from xsv.