// Edit this list with what you don't want
NOT_ALLOWED_LIST = list("ABC", "123", "FOO", ".pdf")
NOT_ALLOWED_LIST_NAME = "NOT_ALLOWED_LIST"

source_string = inquireText("Enter something to be filtered:")

// Begin searching for not-allowed strings
for not_allowed_index = 1 to NOT_ALLOWED_LIST.size
    repeat 
        // Get the first not-allowed string to check
        this_not_allowed_str = getParameterNamed(NOT_ALLOWED_LIST_NAME, not_allowed_index)
        this_not_allowed_len = len(this_not_allowed_str)
        
        // Attempt to find the not-allowed string
        //  - if found, will be non-zero
        //  - if not found, will be zero
        attempt = inStr(source_string, this_not_allowed_str)
        
        // If the not allowed string was found,
        //  - from: the start of the original string (1)
        //  - to:   the attempt index (minus 1 to not include the 1st character)
        //  - PLUS
        //  - from: attempt index + the length of the search string
        //  - to:   the end of what remains
        if attempt <> 0 then
            source_string = subStr(source_string, 1, attempt - 1) + mid(source_string, attempt + this_not_allowed_len)
        endif
    until attempt == 0
    // repeat for all not-allowed strings
next not_allowed_index

// Output
display(source_string)