World: r3wp
[Core] Discuss core issues
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Ladislav 22-Sep-2011 [2265x7] | The COMMENT directive really looks general enough, so it is meaningful to make it standard. Funnily enough, its spelling is: COMMENT , i.e. it is the old word, Robert just wanted to be able to strip-out the COMMENTs from the code, that is why I made it an INCLUDE directive as well. This shows, that currently you can make anything an INCLUDE directive, not just issues. |
Making the COMMENT and INCLUDE directive, we actually keep compatibility with old code, being able to strip-out the COMMENTs from it when wished. | |
Of course, I can imagine a case when the COMMENT directive would be incompatible with the COMMENT function. See e.g. the following: COMMENT 1 + 1 if it is a function (not being stripped out), the expression *is* evaluated as a COMMENT argument. If handled as a directive, and stripped out, it ends up like this: + 1 (the COMMENT 1 part being stripped out), which looks unexpected. But, I was not afraid of such strange things, since nobody uses the COMMENT function like that. | |
Regarding the translation functions: yes, the directives do not suffice to supply all the necessary functionality. Other code is needed to handle the run-time translation of "marked" strings. That code was written by Cyphre and is influencing the behaviour of RebGUI widgets to show the currently required language version of the text. | |
err: "Making the COMMENT *an* INCLUDE directive..." is what it should have been in the text above | |
Aha, actually, forget about it, my definition of the COMMENT directive would handle the 1 + 1 expression as well. The only difference being, that it would be handled during link-time, not run-time of the code, which may still cause some incompatibilities | |
But, as said, I am not afraid of such "stangenesses", since they do not exist in the actual code base | |
Gregg 24-Sep-2011 [2272] | What I mean, regarding %localize.r, is that any script that defines directives (one or more) could use the naming convention. And it makes perfect sense to group related directives in a script. |
Oldes 29-Sep-2011 [2273] | I'm using COMMENT in cases where I want to persist it in my code after building process - as a COMMENT. If I just want to temporaly remove some code, I one or multiple semicolons, which would be exactly the case with 1 + 1 |
Ladislav 29-Sep-2011 [2274] | I'm using COMMENT in cases where I want to persist it in my code after building process - as a COMMENT. - the COMMENT directive supports that mode as well |
sqlab 29-Sep-2011 [2275] | There iis a problem with comment, if you use it in an any block >> print [ [ ; 2 [ 1] 1 but >> print [ [ comment 2 [ 1] ?unset? 1 |
sqlab 30-Sep-2011 [2276] | sorry, I forgot the any >> print any [ [ ; 2 [ 1] 1 >> print any [ [ comment 2 [ 1 [ ] ** Script Error: print is missing its value argument ** Near: print any [ comment 2 1 ] |
Ladislav 30-Sep-2011 [2277] | No problem, it was clear what you were after, and yes, that problem exists |
Ladislav 6-Oct-2011 [2278x6] | As suggested by some people, I am making the COMMENT directive standard, improving all the directives, and enhancing the way how INCLUDE generates/uses errors. When INCLUDE is traversing a large set of files, I feel it convenient not only to get an error, but also the file, where the error occurred. That is possible by either - enhancing the error to contain the information about the file, where it occurred - storing the name of the culprit file somewhere else, not into the error itself |
The former situation (the information about the "culprit file" is stored in the error) looks as follows, currently: performing localization ** User Error: INCLUDE ** Near: do last-error: make error! spec The trouble is, that the present error-forming code does not show all the attributes. If you examine the error on your own, you get: print mold disarm last-error make object! [ code: 802 type: 'user id: 'message arg1: 'syntax arg2: %gui/include.r arg3: [ id: missing arg1: "end-of-block" arg2: "[" arg3: none near: "(line 949) ]" ] near: [do last-error: make error! spec] where: none ] , which shows all the data as "stored" in the error, which is referred (for convenience) by the LAST-ERROR variable | |
aha, correction, the current look of the error is as follows: >>print mold disarm last-error make object! [ code: 802 type: 'user id: 'message arg1: "INCLUDE" arg2: 'syntax arg3: [ file: %actions/tabs/data.r id: missing arg1: "end-of-block" arg2: "[" arg3: none near: "(line 949) ]" ] near: [do last-error: make error! spec] where: none ] | |
The second option would be to not "enhance" the error, in which case it might look like: ** Syntax Error: Missing [ at end-of-script ** Near: (line 949) [ , and examining the error we would get: make object! [ id: missing arg1: "end-of-block" arg2: "[" arg3: none near: "(line 949) ]" ] here, clearly, the information that it was an error in the %actions/tabs/data.r file is missing, but the "standard" error message is more informative. The missing CULPRIT-FILE information could be supplied by defining a CULPRIT-FILE variable for that purpose. Any preference(s) which alternative you might prefer? | |
Summary of the advantages of the first approach: + the file information is present in the error itself Disadvantages: - the error is "too complicated" for the interpreter to display the important informations - the error has to be "intercepted" by TRY for the INCLUDE to be able to "enhance" it. - also, since the INCLUDE works recursively, the TRY is used many times, and the code needs to take care, that the "enhancement" occurs only once | |
The second approach has got the following advantages: + no need to "intercept" the error, since no "error enhancement" needs to be done + the error is displayed by the interpreter in a standard way, the user needs just to get the CULPRIT-FILE name elsewhere Disadvantages: - the error does not contain the CULPRIT-FILE information, which is important, thus, the user needs to look for it elsewhere | |
Gabriele 8-Oct-2011 [2284x3] | Ladislav, it is possible to add new error kinds to system/error, then the "error display" can be made to show what you want as well. |
eg. see http://www.rebol.it/power-mezz/schemes/hardball.html#section-7.1 | |
and http://www.rebol.it/power-mezz/mezz/messages.html#section-9 | |
Ladislav 8-Oct-2011 [2287x3] | Ladislav, it is possible to add new error kinds to system/error, then the error display" can be made to show what you want as well." - yes, in R2, but INCLUDE is written to be compatible with R3 |
(I used such a method when INCLUDE was meant just for R2, but, with R3 I am not sure) | |
Brian, don't you happen to know a similar "mechanism" for R3? | |
Robert 8-Oct-2011 [2290x2] | ; the arguments have to be strings: substitute [ %1" 12] ; triggers an error" - Why does the STRING! constraint exist? IMO every aregument should be reduced and than formed into a string. |
The FORM can be implicit if the argument is not string. | |
Ladislav 8-Oct-2011 [2292x7] | Why does the STRING! constraint exist? - Cyphre and I thought, that it may be of help for the programmer to tell him that he "forgot" to put in strings. Even the numbers are unlikely to be put in unformatted. |
IMO every aregument should be reduced and than formed into a string. - yes, but that should be done when a substitution is made, not when it is translated, e.g. | |
I think that it may help to think of substitutions as "a different kind of string". A substitution as "a different kind of string" does not need to contain any expressions or code. | |
Certainly, this restriction can be removed, but it does not look like worth doing it. | |
Substitutions are meant to separate: - the time when the substition was created (using e.g. the REDUCE function) - the time when the substitution was translated and displayed (using e.g. the combination of the TRANSLATE SUBSTITUTE and SHOW functions) | |
Note: it may make sense to put some of the Q&A to the http://www.rebol.net/wiki/Replacement#SUBSTITUTE section | |
We can also think of the SUBSTITUTE function as being written using the KISS strategy. REDUCE can be performed separately, that is why it is not needed in the definition of the SUBSTITUTE function. | |
GrahamC 8-Oct-2011 [2299x4] | substitute ["a%0"] ; == "aa%0" but there is no argument string? |
Isn't this just a special case of printf .. so why not implement printf instead? | |
I agree with Robert .. why would you want to perform an extra reduce ? Is the added efficiency worthwhile making the program reduce in those instances where non string values are being passed? | |
KISS in this instance means default reduce, and use a refinement if you don't want this behaviour | |
Ladislav 8-Oct-2011 [2303x12] | Isn't this just a special case of printf .. so why not implement printf instead? - it does not have anything in common with printf, except for the superficial similarity |
I agree with Robert .. why would you want to perform an extra reduce ? - exactly because the REDUCE is performed at a different time | |
The substitution has to be performed always at the translation time, while REDUCE just when you need to create the substitution | |
Not to mention, that it is safer to have substitutions as data files, than to allow code | |
err. susbstitutions as data values is what I mean | |
there is no argument string? - the %0 is the substitution string (the first one), just as a curiosity, it may not be needed | |
(you do not have to use %0 if you don't need to) | |
KISS in this instance means default reduce, and use a refinement if you don't want this behaviour - well, that is very much like saying, that e.g. for the TEXT widget in the Laout dialect you prefer to use a code block, which should (re)generate the string to be displayed every time it is SHOWn. While possible, it is not KISS | |
I have to repeat, that the goal here is to represent text, that needs to be translated, and we found out, that "generated strings" cannot be represented as strings to be translatable. | |
As an example, check this: ["You do not have sufficient rights to delete the '%1" file." "database.r"] This is easy to translate, since only the substitution strings needs a translation, while the argument does not. If you know how to translate the substitution string, the argument string does not matter at all. | |
So, the TRANSLATE function just replaces the substitution string by a different language version, leaving the argument as-is, e.g.: ["Sie verfuegen nicht die ausreichende Zugriffsrechte fuer das File '%1' zu loeschen." "database.r"] (forgive my attempt, I bet it is not a correct German) | |
Originally, the block might have been generated by something like: my-substitution: reduce ["You do not have sufficient rights to delete the '%1" file." to string! file] | |
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