i want to do something like this: Transcript show: '\n'. how?
Use the following:
Transcript cr
You can use it after a value via a cascade:
Transcript show: 123; cr
From my (long) experience, missing character escapes are one of the few things that are missing in Smalltalk. For streaming, solutions using cr, tab etc. are ok.
However, if you need a particular control character in a string, this may be ugly and hard to read (using "streamContents:", or "withCRs" to add a newLine). Alternatively, you may want to use one of the (non-standard) string expansion mechanisms. For example, in VisualWorks or Smalltalk/X, you can write (if I remember correctly):
'someString with newline<n>and<t>tabs' expandMacros
or even with printf-like slicing of other object's printStrings:
'anotherString<n><t>with newlines<n>and<t>tabs and<p>' expandMacrosWith:(Float pi)
I guess, there is something similar in Squeak and V'Age as well.
But, be aware: these expansions are done at execution time. So you may encounter a penalty when heavily using them on many strings.
The character itself can be reached as Character cr. So, you could also do this:
Transcript show: 'Bla! , Character cr asString.
But of course,
Transcript show: 'Bla!' ; cr.
is way more elegant.
What I do as a convenience is add a method "line" to the String class:
line
^self, String lf
Then you can just say obj showSomething: 'Hello world!' line.
Or call it newline, endl, lf, etc...
Related
Sorry if this is documented somewhere, but I haven't been able to find it. When using brace delimiters with qq, code is not interpolated:
qq.raku
#!/usr/bin/env raku
say qq{"Two plus two": { 2 + 2 }};
say qq["Two plus two": { 2 + 2 }];
$ ./qq.raku
"Two plus two": { 2 + 2 }
"Two plus two": 4
Obviously, this isn't a big deal since I can use a different set of delimiters, but I ran across it and thought I'd ask.
Update
As #raiph pointed out, I forgot to put the actual question: Is this the way it's supposed to work?
The quote language "nibbler" (the bit of the grammar that eats its way through a quoted string) looks like this:
[
<!stopper>
[
|| <starter> <nibbler> <stopper>
|| <escape>
|| .
]
]*
That is, until we see a stopper, eat whichever comes first of:
A starter (the opening { in your case), followed by some internal stuff, followed by a stopper (the }); this allows for nesting of the construct inside of the string
An escape (and closure interpolation is considered a kind of escape)
Any other character
This ordering in the grammar means that a nesting of the chosen quote starter/stopper will always win over an escape. This issue was discussed during the language design; we could, after all, have reordered the alternation in the grammar to have escapes win. On balance, however, it was felt that the choice of starter/stopper was the more local decision than the general properties of the quoting language, and so should take precedence. (This is also consistent with how quote languages are constructed: we take the base quoted string grammar and mix starter/stopper methods into it.)
Obviously, this isn't a big deal since I can use a different set of delimiters, but I ran across it and thought I'd ask.
You didn't ask anything. :)
Let's say you've got some text. And you want to use double quote processing to get interpolation, except you don't want braced text to be interpolated as code. You could write, say, qq:!c '...'. But don't you think it's a lot easier to remember, write, and read qq{ ... }?
Nice little touch, right?
Which is why it's the way it is -- it's a very nice touch.
And, perhaps, why it's not documented -- it's little, and, once you encounter it, obvious what you need to do.
That said, the Q lang escapes include ones to recursively re-enter the Q lang:
say qq{"Two plus two": \qq[{ 2 + 2 }] }; # "Two plus two": 4
Does that answer your question? :)
I'm trying to write a simple multi-line Alias that says several predefined strings of characters in mIRC. The problem is that the strings can contain:
{
}
|
which are all used in the scripting language to group sections of code/commands. So I was wondering if there was an escape character I could use.
In lack of that, is there a method, or alternative way to be able to "say" multiple lines of these strings, so that this:
alias test1 {
/msg #　samplestring}contains_chars|
/msg # _that|break_continuity}{
}
Outputs this on typing /test1 on a channel:
<MyName> samplestring}contains_chars|
<MyName> _that|break_continuity}{
It doesn't have to use the /msg command specifically, either, as long as the output is the same.
So basically:
Is there an escape character of sorts I can use to differentiate code from a string in mIRC scripting?
Is there a way to tell a script to evaluate all characters in a string as a literal? Think " " quotes in languages like Java.
Is the above even possible using only mIRC scripting?
"In lack of that, is there a method, or alternative way to be able to "say" multiple lines of these strings, so that this:..."
I think you have to have to use msg # every time when you want to message a channel. Alterativelty you can use the /say command to message the active window.
Regarding the other 3 questions:
Yes, for example you can use $chr(123) instead of a {, $chr(125) instead of a } and $chr(124) instead of a | (pipe). For a full list of numbers you can go to http://www.atwebresults.com/ascii-codes.php?type=2. The code for a dot is 46 so $chr(46) will represent a dot.
I don't think there is any 'simple' way to do this. To print identifiers as plain text you have to add a ! after the $. For example '$!time' will return the plain text '$time' as $time will return the actual value of $time.
Yes.
I'm trying to make a console-based program that makes use of ANSI escape codes with GNU Smalltalk. I can't seem to figure out how to go about printing a string object formatted with ANSI escape codes. I've tried the following.
'\x1b[31mHi' displayNl
This prints the entire string, including the escape code, without any formatting. I would have expected this to print "Hi" in red (and then everything else in the console after that, as I didn't reset the color.)
After googling a bit, I was able to find a couple issues on mailing lists where people were trying to produce things like newlines using "\n". Most of the answers were using the Transcript object's cr method, but I didn't find anything about colors in the textCollector class.
It looks like it shouldn't be all that hard to create my own module in C to achieve this functionality, but I'd like to know if there's a better way first.
I'm aware of the ncurses bindings, but I'm not sure that'd be practical for just making certain pieces of text in the program colored. So, is there a standard way of outputting colored text to the terminal in GNU Smalltalk using ANSI escape sequences?
Ended up getting an answer on the GNU Smalltalk mailing list. Looks like you can use an interpolation operator to achieve this.
For example ('%1[31mHi' % #($<16r1B>)) displayNl. would change the color to red, and ('%1[34mHi' % #($<16r1B>)) displayNl. would change the color to blue.
Basically, the % operator looks for a sequences that look like "%(number)" and replaces them with the objects in the array to the right of the operator. In our case, the array has one item, which is the ascii escape character in hexadecimal. So the "%1" in "%1[31mHi' is being replaced with the escape character, and then printed.
(This answer was stolen almost verbatim from Paolo on the GNU Smalltalk mailing list.)
I have made a program which takes a 1000 digit number as input.
It is fixed, so I put this input into the code file itself.
I would obviously be storing it as Integer type, but how do I do it?
I have tried the program by having 1000 digits in the same line. I know this is the worst possible code format! But it works.
How can assign the variable this number, and split its lines. I read somewhere something about eos? Ruby, end of what?
I was thinking that something similar to comments could be used here.
Help will be appreciated.
the basic idea is to make this work:
a=3847981438917489137897491412341234
983745893289572395725258923745897232
instead of something like this:
a=3847981438917489137897491412341234983745893289572395725258923745897232
Haskell doesn't have a way to split (non-String) literals across multiple lines. Since Strings are an exception, we can shoehorn in other literals by parsing a multiline String:
v = read
"32456\
\23857\
\23545" :: Integer
Alternately, you can use list syntax if you think it's prettier:
v = read . concat $
["32456"
,"24357"
,"23476"
] :: Integer
The price you pay for this is that some work will be done (once) at runtime, namely, the parsing (e.g. read).
I want to verify that a given file in a path is of type text file, i.e. not binary, i.e. readable by a human. I guess reading first characters and check each character with :
isAlphaNumeric
isSpecial
isSeparator
isOctetCharacter ???
but joining all those testing methods with and: [ ... and: [ ... and: [ ] ] ] seems not to be very smalltalkish. Any suggestion for a more elegant way?
(There is a Python version here How to identify binary and text files using Python? which could be useful but syntax and implementation looks like C.)
only heuristics; you can never be really certain...
For ascii, the following may do:
|isPlausibleAscii numChecked|
isPlausibleAscii :=
[:char |
((char codePoint between:32 and:127)
or:[ char isSeparator ])
].
numChecked := text size min: 1024.
isPossiblyText := text from:1 to:numChecked conform: isPlausibleAscii.
For unicode (UTF8 ?) things become more difficult; you could then try to convert. If there is a conversion error, assume binary.
PS: if you don't have from:to:conform:, replace by (copyFrom:to:) conform:
PPS: if you don't have conform: , try allSatisfy:
All text contains more space than you'd expect to see in a binary file, and some encodings (UTF16/32) will contain lots of 0's for common languages.
A smalltalky solution would be to hide the gory details in method on Standard/MultiByte-FileStream, #isProbablyText would probably be a good choice.
It would essentially do the following:
- store current state if you intend to use it later, reset to start (Set Latin1 converter if you use a MultiByteStream)
Iterate over N next characters (where N is an appropriate number)
Encounter a non-printable ascii char? It's probably binary, so return false. (not a special selector, use a map, implement a new method on Character or something)
Increase 2 counters if appropriate, one for space characters, and another for zero characters.
If loop finishes, return whether either of the counters have been read a statistically significant amount
TLDR; Use a method to hide the gory details, otherwise it's pretty much the same.