property |NSURL| : a reference to current application’s |NSURL|
property NSData : a reference to current application’s NSData
property NSJSONSerialization : a reference to current application’s NSJSONSerialization

set aInfo to retValueInBTC("JPY", "10000") of me
–>　　"0.00654764"

on retValueInBTC(aCurrency, aVal)
　　set aRec to {currency:aCurrency, value:aVal}
　　set reqURLStr to "https://blockchain.info/tobtc"
　　set aURL to retURLwithParams(reqURLStr, aRec) of me
　　try
　　　　with timeout of 10 seconds
　　　　　　set curl_command to "curl " & quoted form of aURL
　　　　　　set jRes to do shell script curl_command
　　　　　　return jRes
　　　　end timeout
　　on error
　　　　return missing value
　　end try
end retValueInBTC

on retURLwithParams(aBaseURL, aRec)
　　set aDic to current application’s NSMutableDictionary’s dictionaryWithDictionary:aRec
　　
　　set aKeyList to (aDic’s allKeys()) as list
　　set aValList to (aDic’s allValues()) as list
　　set aLen to length of aKeyList
　　
　　set qList to {}
　　repeat with i from 1 to aLen
　　　　set aName to contents of item i of aKeyList
　　　　set aVal to contents of item i of aValList
　　　　set the end of qList to (current application’s NSURLQueryItem’s queryItemWithName:aName value:aVal)
　　end repeat
　　
　　set aComp to current application’s NSURLComponents’s alloc()’s initWithString:aBaseURL
　　aComp’s setQueryItems:qList
　　set aURL to (aComp’s |URL|()’s absoluteString()) as text
　　
　　return aURL
end retURLwithParams