R: multiline shell command with embedded quotes - r

Question

Seems like this should be very simple, but I cannot get it to work. I have a long shell command that I would like to span over multiple lines, but escaping the single/double quotes correctly is giving me trouble. I have searched SO and googled this, but cannot find the solution.
Original, working code:
getVersion <- function() {
version <- shell("powershell -Command $path = 'C:/Windows/notepad.exe'; $versioninfo = [System.Diagnostics.FileVersionInfo]::GetVersionInfo($path); $itemproperties= get-childitem $path; [pscustomobject]#{'File version' = $versioninfo.FileVersion}", intern = TRUE)
version <- gsub(" ", "", version[4])
return(version)
}
Does not work:
getVersion <- function() {
version <- shell(paste0(\""powershell -Command $path = 'C:/Windows/notepad.exe'; $versioninfo = [System.Diagnostics.FileVersionInfo]::GetVersionInfo($path);\",
\"$itemproperties= get-childitem $path; [pscustomobject]#{'File version' = $versioninfo.FileVersion}"\"), intern = TRUE)
version <- gsub(" ", "", version[4])
return(version)
}
Also tried this:
getVersion <- function() {
version <- paste0('shell(\"powershell -Command $path = "C:/Windows/notepad.exe"; $versioninfo = [System.Diagnostics.FileVersionInfo]::GetVersionInfo($path);',
'$itemproperties= get-childitem $path; [pscustomobject]#{"File version" = $versioninfo.FileVersion}\", intern = TRUE)')
version <- gsub(" ", "", version[4])
return(version)
}

Answer 1

Why are you trying to escape? You don't actually have double quotes in the string you need to pass, right? So you can just do a paste() with double quoted strings that happen to contain single quotes. Or am I missing something?
For example, would this work?
getVersion <- function() { version <- shell(paste("powershell -Command $path = 'C:/Windows/notepad.exe';",
"$versioninfo = [System.Diagnostics.FileVersionInfo]::GetVersionInfo($path);‌​",
"$itemproperties= get-childitem $path;",
"[pscustomobject]#{'File version' = $versioninfo.FileVersion}"),
intern = TRUE)
version <- gsub(" ", "", version[4])
return(version) }