gsubfn function not giving desired output when ignore.case = TRUE

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I am trying to substitute multiple patterns within a character vector with their corresponding replacement strings. After doing some research I found the package gsubfn which I think is able to do what I want it to, however when I run the code below I don't get my expected output (see end of question for results versus what I expected to see). 

library(gsubfn)

# Our test data that we want to search through (while ignoring case)

test.data<- c("1700 Happy Pl","155 Sad BLVD","82 Lolly ln", "4132 Avent aVe")

#     A list data frame which contains the patterns we want to search for 
#     (again ignoring case) and the associated replacement strings we want to 
#     exchange any matches we come across with.


frame<- data.frame(pattern= c(" Pl"," blvd"," LN"," ave"), replace= c(" Place", " Boulevard", " Lane", " Avenue"),stringsAsFactors = F)

# NOTE: I added spaces in front of each of our replacement terms to make
#       sure we only grab matches that are their own word (for instance if an
#       address was 45 Splash Way we would not want to replace "pl" inside of 
#       "Splash" with "Place

#     The following set of paste lines are supposed to eliminate the substitute function from
#     grabbing instances like first instance of " Ave" found directly after "4132" 
#     inside "4132 Avent Ave" which we don't want converted to " Avenue".

pat <- paste(paste(frame$pattern,collapse = "($|[^a-zA-Z])|"),"($|[^a-zA-Z])", sep = "")

#     Here is the gsubfn function I am calling
gsubfn(x = test.data, pattern = pat, replacement = setNames(as.list(frame$replace),frame$pattern), ignore.case = T)

Output being received:

[1] "1700 Happy" "155 Sad"    "82 Lolly"   "4132 Avent"

Output expected:

[1] "1700 Happy Place" "155 Sad Boulevard" "82 Lolly Lane" "4132 Avent Avenue"

My working theory on why this isn't working is that the matches don't match the names associated with the list I am passing into the gsubfn's replacement argument because of some case discrepancies (eg: the match being found on "155 Sad BLVD" doesn't == " blvd" even though it was able to be seen as a match due to the ignore.case argument). Can someone confirm that this is the issue/point me to what else might be going wrong, and perhaps a way of fixing this that doesn't require me expanding my pattern vector to include all case permutations if possible?

gsub r case-sensitive replace
1 Answers

Seems like stringr has a simple solution for you:

library(stringr)

str_replace_all(test.data, 
                regex(paste0('\\b',frame$pattern,'$'),ignore_case = T),
                frame$replace)
#[1] "1700 Happy Place"  "155 Sad Boulevard" "82 Lolly Lane"     "4132 Avent Avenue"

Note that I had to alter the regex to look for only words at the end of the string because of the tricky 'Avent aVe'. But of course there's other ways to handle that too.

user_52897530
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