Updated Answer:
The code below it what I'd use to replace the original code offered as there appears to be a bug in AppleScript when using the do shell script command in the manner originally presented that isn't present went the code, in a representative manner, is run in a bash script in Terminal.
Note that anytimeopen for access is used, it needs to be coded to trap any errors and try and close the file, which this attempts to do. That said it is not necessarily then only error handling I'd employ and all coding answer I present are done so as proof of concept and the onus to write code employing reasonable error handing is yours to fulfill.
As coded, this will create the target file if it doesn't exist while adding the text to add to it and if it does exist, places the text to add as the top line of the target file.
set targetFilePathname to (POSIX path of (path to desktop as string) & "My Fruit Log.txt")
-- # set theTextToWrite to "This text will be written at the top of the file." & "\n"
set theTextToWrite to "This text will be written at the top of the file." & "\n"
set theOriginalText to ""
try
set theOriginalText to (read targetFilePathname) as string
end try
-- # set theTextToWrite to theTextToWrite & "\n" & theOriginalText
set theTextToWrite to theTextToWrite & "\n" & theOriginalText
try
set referenceNumber to open for access targetFilePathname with write permission
write theTextToWrite to referenceNumber starting at 0
close access referenceNumber
on error eStr number eNum
display dialog eStr & " number " & eNum buttons {"OK"} default button 1 with title "File I/O Error..." with icon caution
try
close access referenceNumber
end try
return
end try
Running the following AppleScript code in AppleScript Editor:
set theText to "I ate an apple at 11:54 pm without the skin."
set theTime to do shell script "awk -F ' at | am | pm ' '{print $2}'<<<" & quoted form of theText
log "The time was: " & theTime
set theText to "I ate two navel oranges at 6:30 am with a glass of water."
set theTime to do shell script "awk -F ' at | am | pm ' '{print $2}'<<<" & quoted form of theText
log "The time was: " & theTime
Produces the following output in the AppleScript Editor's Event Log:
tell current application
do shell script "awk -F ' at | am | pm ' '{print $2}'<<<'I ate an apple at 11:54 pm without the skin.'"
--> "11:54"
(*The time was: 11:54*)
do shell script "awk -F ' at | am | pm ' '{print $2}'<<<'I ate two navel oranges at 6:30 am with a glass of water.'"
--> "6:30"
(*The time was: 6:30*)
end tell
In the above examples I've defined the field separators (delimiters) in awk using the -F option as ' at | am | pm ' which equates to " at ", " am " and " pm " and it prints '{print $2}' what's between the field separators.
Note: The use of the log command is not necessary to the coding for the answer and is being used just to show what the value of theTime contains for the Event Log output aside from what's shown after -->, which is the result as normally shown in the Event Log.
Update: I wrote my original answer based on a literal interpretation in that when said, "So, I would like the opening text item delimiter to be at_ and the closing text item delimiter to be either _pm or _am", what was wanted was to literally use those as the delimiters. However, since a different solution using pure AppleScript code, in a separate answer, was presented, let me present a one-line AppleScript code solution that does the same thing the 8 lines of pure AppleScript code does and by focusing on the colon, but as as part of a RegEx representation of the time in hours and minutes.
set theTime to do shell script "awk 'match($0,/[0-9]{1,2}:[0-5][0-9]/) {print substr($0,RSTART,RLENGTH)}'<<<" & quoted form of theText
Running the following AppleScript code in AppleScript Editor:
set theText to "I ate an apple at 11:54 pm without the skin."
set theTime to do shell script "awk 'match($0,/[0-9]{1,2}:[0-5][0-9]/) {print substr($0,RSTART,RLENGTH)}'<<<" & quoted form of theText
set theText to "I ate two navel oranges at 6:30 am with a glass of water."
set theTime to do shell script "awk 'match($0,/[0-9]{1,2}:[0-5][0-9]/) {print substr($0,RSTART,RLENGTH)}'<<<" & quoted form of theText
Produces the following output in the AppleScript Editor's Event Log:
tell current application
do shell script "awk 'match($0,/[0-9]{1,2}:[0-5][0-9]/) {print substr($0,RSTART,RLENGTH)}'<<<'I ate an apple at 11:54 pm without the skin.'"
--> "11:54"
do shell script "awk 'match($0,/[0-9]{1,2}:[0-5][0-9]/) {print substr($0,RSTART,RLENGTH)}'<<<'I ate two navel oranges at 6:30 am with a glass of water.'"
--> "6:30"
end tell
As you can see, whether or not there are one to two numbers preceding the colon the RegEx matches and the awk program returns the desired match, of which being the time.
Personally, I'd choose to use this particular method over my original answer, as it's a better method under the circumstances, and or over the pure AppleScript code as I can't justify writing 8 lines of pure AppleScript code when a single line of regular AppleScript code produces the same results as the 8 lines do!
Best Answer
You can use something like this:
There's more info about
dateand its modifiers at cyberciti.