AppleScript 并不容易：
log 仅 在 AppleScript 编辑器中运行或通过 osascript 运行时（在这种情况下为 stderr）记录 - 在其他情况下输出将丢失，例如就像应用程序使用 NSAppleScript Cocoa 类运行脚本一样。
log 只接受 一个 参数；虽然它确实接受任何对象类型，但它并不容易获得非内置类型的有意义表示：例如，尝试log me 获取有关脚本本身的信息；通常，必须使用log (get properties of <someObj>) 来获取有意义的信息；请注意繁琐的语法，这是必需的，因为仅使用 log properties of <someObj> 通常只打印 参考表单的名称 而不是它指向的属性（例如，log properties of me 无用地只输出 (*properties*) )。
me as text。
以下是解决这些问题的辅助子例程：
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dlog() 是一个子例程，它将派生任何对象的有意义的文本表示与基于全局配置变量写入多个日志目标（包括系统日志和文件）的能力相结合。
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toString()（有效嵌入在dlog() 中）是一个子例程，它接受任何类型的单个对象并从中派生出有意义的文本表示。
向@1.61803 致敬；他的回答为实现各种日志目标提供了指导。
示例：
# Setup: Log to syslog and a file in the home dir.
# Other targets supported: "log", "alert"
# Set to {} to suppress logging.
set DLOG_TARGETS to { "syslog", "~/as.log" }
# Log properties of the front window of frontmost application.
dlog(front window of application (path to frontmost application as text))
# Log properties of own front window; note the *list* syntax for multiple args.
dlog({"my front window: ", front window})
# Get properties of the running script as string.
toString(me) # ->, e.g.: [script name="sandbox"] {selection:insertion point after character 2475 of text of document "sandbox2.scpt", frontmost:true, class:application, name:"AppleScript Editor", version:"2.6"}
详情请参见每个子例程上方的源代码 cmets。
dlog() 源代码
# Logs a text representation of the specified object or objects, which may be of any type, typically for debugging.
# Works hard to find a meaningful text representation of each object.
# SYNOPSIS
# dlog(anyObjOrListOfObjects)
# USE EXAMPLES
# dlog("before") # single object
# dlog({ "front window: ", front window }) # list of objects
# SETUP
# At the top of your script, define global variable DLOG_TARGETS and set it to a *list* of targets (even if you only have 1 target).
# set DLOG_TARGETS to {} # must be a list with any combination of: "log", "syslog", "alert", <posixFilePath>
# An *empty* list means that logging should be *disabled*.
# If you specify a POSIX file path, the file will be *appended* to; variable references in the path
# are allowed, and as a courtesy the path may start with "~" to refer to your home dir.
# Caveat: while you can *remove* the variable definition to disable logging, you'll take an additional performance hit.
# SETUP EXAMPLES
# For instance, to use both AppleScript's log command *and* display a GUI alert, use:
# set DLOG_TARGETS to { "log", "alert" }
# Note:
# - Since the subroutine is still called even when DLOG_TARGETS is an empty list,
# you pay a performancy penalty for leaving dlog() calls in your code.
# - Unlike with the built-in log() method, you MUST use parentheses around the parameter.
# - To specify more than one object, pass a *list*. Note that while you could try to synthesize a single
# output string by concatenation yourself, you'd lose the benefit of this subroutine's ability to derive
# readable text representations even of objects that can't simply be converted with `as text`.
on dlog(anyObjOrListOfObjects)
global DLOG_TARGETS
try
if length of DLOG_TARGETS is 0 then return
on error
return
end try
# The following tries hard to derive a readable representation from the input object(s).
if class of anyObjOrListOfObjects is not list then set anyObjOrListOfObjects to {anyObjOrListOfObjects}
local lst, i, txt, errMsg, orgTids, oName, oId, prefix, logTarget, txtCombined, prefixTime, prefixDateTime
set lst to {}
repeat with anyObj in anyObjOrListOfObjects
set txt to ""
repeat with i from 1 to 2
try
if i is 1 then
if class of anyObj is list then
set {orgTids, AppleScript's text item delimiters} to {AppleScript's text item delimiters, {", "}} # '
set txt to ("{" & anyObj as string) & "}"
set AppleScript's text item delimiters to orgTids # '
else
set txt to anyObj as string
end if
else
set txt to properties of anyObj as string
end if
on error errMsg
# Trick for records and record-*like* objects:
# We exploit the fact that the error message contains the desired string representation of the record, so we extract it from there. This (still) works as of AS 2.3 (OS X 10.9).
try
set txt to do shell script "egrep -o '\\{.*\\}' <<< " & quoted form of errMsg
end try
end try
if txt is not "" then exit repeat
end repeat
set prefix to ""
if class of anyObj is not in {text, integer, real, boolean, date, list, record} and anyObj is not missing value then
set prefix to "[" & class of anyObj
set oName to ""
set oId to ""
try
set oName to name of anyObj
if oName is not missing value then set prefix to prefix & " name=\"" & oName & "\""
end try
try
set oId to id of anyObj
if oId is not missing value then set prefix to prefix & " id=" & oId
end try
set prefix to prefix & "] "
set txt to prefix & txt
end if
set lst to lst & txt
end repeat
set {orgTids, AppleScript's text item delimiters} to {AppleScript's text item delimiters, {" "}} # '
set txtCombined to lst as string
set prefixTime to "[" & time string of (current date) & "] "
set prefixDateTime to "[" & short date string of (current date) & " " & text 2 thru -1 of prefixTime
set AppleScript's text item delimiters to orgTids # '
# Log the result to every target specified.
repeat with logTarget in DLOG_TARGETS
if contents of logTarget is "log" then
log prefixTime & txtCombined
else if contents of logTarget is "alert" then
display alert prefixTime & txtCombined
else if contents of logTarget is "syslog" then
do shell script "logger -t " & quoted form of ("AS: " & (name of me)) & " " & quoted form of txtCombined
else # assumed to be a POSIX file path to *append* to.
set fpath to contents of logTarget
if fpath starts with "~/" then set fpath to "$HOME/" & text 3 thru -1 of fpath
do shell script "printf '%s\\n' " & quoted form of (prefixDateTime & txtCombined) & " >> \"" & fpath & "\""
end if
end repeat
end dlog
toString() 源代码
# Converts the specified object - which may be of any type - into a string representation for logging/debugging.
# Tries hard to find a readable representation - sadly, simple conversion with `as text` mostly doesn't work with non-primitive types.
# An attempt is made to list the properties of non-primitive types (does not always work), and the result is prefixed with the type (class) name
# and, if present, the object's name and ID.
# EXAMPLE
# toString(path to desktop) # -> "[alias] Macintosh HD:Users:mklement:Desktop:"
# To test this subroutine and see the various representations, use the following:
# repeat with elem in {42, 3.14, "two", true, (current date), {"one", "two", "three"}, {one:1, two:"deux", three:false}, missing value, me, path to desktop, front window of application (path to frontmost application as text)}
# log my toString(contents of elem)
# end repeat
on toString(anyObj)
local i, txt, errMsg, orgTids, oName, oId, prefix
set txt to ""
repeat with i from 1 to 2
try
if i is 1 then
if class of anyObj is list then
set {orgTids, AppleScript's text item delimiters} to {AppleScript's text item delimiters, {", "}}
set txt to ("{" & anyObj as string) & "}"
set AppleScript's text item delimiters to orgTids # '
else
set txt to anyObj as string
end if
else
set txt to properties of anyObj as string
end if
on error errMsg
# Trick for records and record-*like* objects:
# We exploit the fact that the error message contains the desired string representation of the record, so we extract it from there. This (still) works as of AS 2.3 (OS X 10.9).
try
set txt to do shell script "egrep -o '\\{.*\\}' <<< " & quoted form of errMsg
end try
end try
if txt is not "" then exit repeat
end repeat
set prefix to ""
if class of anyObj is not in {text, integer, real, boolean, date, list, record} and anyObj is not missing value then
set prefix to "[" & class of anyObj
set oName to ""
set oId to ""
try
set oName to name of anyObj
if oName is not missing value then set prefix to prefix & " name=\"" & oName & "\""
end try
try
set oId to id of anyObj
if oId is not missing value then set prefix to prefix & " id=" & oId
end try
set prefix to prefix & "] "
end if
return prefix & txt
end toString