How can you get the current terminal line (the one that is still editable by the user)?

I need a way to use the current line which the users typed into as variable for a shell function. my current code, which can be called by ctrl+r zle -N search bindkey "^R" search search () { read str; fc -ln -30 | grep $(printf "%q\n" "$str"); } or simply, to call it as a function search () { fc -ln -30 | grep $(printf "%q\n" "$1"); } updated: target pseudo code, to call as a function called by ctrl+r that needs no further input prompt zle -N search bindkey "^R" search search () echo ""; #for better formatting because ctrl+R is not enter so the BUFFER(current line) gets corrupted and looks messy and the current input is not correctly shown fc -ln -30 | grep $(printf "%q\n" "$BUFFER"); #edited to be the solution where $BUFFER is the current terminal line }