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[REBOL] Java scanners vs rebol

From: hallvard::ystad::oops-as::no at: 8-Dec-2004 0:33

Hello list, I still read some Java news every now and then, and last week, I came across these: Here's a synopsis: As some of you must know, reading a URL with Java is a time consuming enterprise: InputStream source = new URL("http://some.url/path/file.html").openStream(); BufferedReader br = new BufferedReader( new InputStreamReader( source ) ); String text = ""; for ( String line; (line = br.readLine()) ! = null ) text.concat( line ); Now, finally, Java introduces a new class that can turn this into a one-liner (according to Pat Niemeyer): String text = new Scanner(new URL("http://some.url/path/file.html").openStream()).useDelimiter("\\A").next(); (Pat only put in the variable "source" to construct the Scanner, so I had to replace it with the URL constructor. Nice one-liner, eh?) I send this not only to make fun of the Java programming language, but also to remind us all of the really neat simplicity we have in rebol: text: read http://some.url/path/file.html I also advice you to read the JDCTechTip about the scanner class. It seems to behave a bit like 'parse does when not using a rule but a set of delimiters. Only Java (using Java.util.Scanner) needs 41 lines of code to do this: Assume you have these lines in a file named Joe, 38, true Kay, 27, true Lou, 33, false To produce this output: It is true that Joe, age 38, is certified. It is true that Kay, age 27, is certified. It is false that Lou, age 33, is certified. You need 10 lines of code in Rebol: REBOL [] either system/script/args [ text: read to-file system/script/args foreach [name age certified?] parse text "^/" [ print ["It is" certified? "that" name "age" age "is certified"] ] ][ print "usage: short.r filename" ] HY