## Here is an example for Javascript.

syntax "javascript" "\.js$"
comment "//"

color brightred "\<[A-Z_][0-9A-Z_]+\>"
color green "\<(const|function|let|this|typeof|var|void)\>"
color brightyellow "\<(for|if|while|with|do|else|case|default|switch)\>"
color brightyellow "\<(export|try|throw|catch|new|delete)\>"
color magenta "\<(continue|break|return|yield)\>"
color brightmagenta "'([^'\]|(\\["'abfnrtv\\]))'" "'\\(([0-3]?[0-7]{1,2}))'" "'\\x[0-9A-Fa-f]{1,2}'"

# Strings.
color brightyellow "<[^= 	]*>" ""(\\.|[^"])*"" "'(\\.|[^'])*'"
# Comments.
color brightblue "//.*"
color brightblue start="/\*" end="\*/"

# Trailing whitespace.
color ,green "[[:space:]]+$"