Improved the substitution pattern

The history number is printed as "%5d" so we need to handle all possible
columns.

    declare -a lines=(
        "10000  history 1"
        " 1000  history 1"
        "    1  history 1"
        " 1000* history 1"
        " 1000   history 1"
    )

    for line in "${lines[@]}"; do
        echo "${line#*[[:digit:]][* ] }"
    done

bash-preexec.sh

@@ -251,7 +251,7 @@ __bp_preexec_invoke_exec() {
 
     local this_command
     this_command=$(LC_ALL=C HISTTIMEFORMAT='' builtin history 1)
-    this_command="${this_command# *[[:digit:]]*[* ] }"
+    this_command="${this_command#*[[:digit:]][* ] }"
 
     # Sanity check to make sure we have something to invoke our function with.
     if [[ -z "$this_command" ]]; then