OpenEuphoria

2. Re: Isn't this wrong?

• Posted by DerekParnell (admin) Jul 25, 2010
• 1081 views

 
atom retry 

<0025>:: a name is expected here 
atom retry 

The word retry is a reserved word in Eu 4. It can be used inside loops to repeat the current iteration.

 
atom retry2 
retry2 = 0 
 
with trace 
trace(1) 
 
while 1 do 
 
     if retry2 then end 
 
     if 
       
end while 

The 'dangling' if is not really dangling. The IF statement must end with the two words 'end' and 'if' and they do not have to be on the same line.

eg.

-- First statement 
if 
1 
then 
? 1 
end 
if 
 
-- Second statement 
if 1 then ? 1 end if 

Both statements above are identical as far as Eu is concerned.

 
sequence TheWebPage 
TheWebPage = "" 
 
atom retry2 
retry2 = 0 
 
with trace 
trace(1) 
 
while 1 do 
 
 
     if match(upper("<title>404 - Page Not Found</title>"),upper(TheWebPage)) then  
       TheWebPage = "404" 
       exit 
     end 
 
 
     if retry2 then end 
 
     if 
       
end while 

Syntax error - expected to see =, +=, -=, *=, /= or &=\\ 
     if retry2 then end\\ 
                   ^\\ 

<0076>:: expected to see an assignment after 'retry2', such as =, +=, -=, *=, /= 
 or &= 
     if retry2 then end 
                   ^ 

Ok, the error pointer could be improved. Currently the scanner has gotten to the end of the word 'then' and the parser has by now realized that an assignment is required so the error message is correct "expecting to see an assignment" and the '^' pointer is showing you where the scanner is up to. It is sort of saying, "Hey I got 'then' but was expecting some sort of assignment there instead".

Now it was expecting an assignment because the previous IF statement actually uses the 'if' preceding the 'retry2' word as marking the end of the IF statement. Thus 'retry2' is the start of a new statement and the only type of statements that start with a variable are assignment statements.

It seems that you have mistakenly thought that the IF statement was completed by the 'end' word alone, but that is not the case. Look at it laid out differently ...

sequence TheWebPage 
TheWebPage = "" 
 
atom retry2 
retry2 = 0 
 
with trace 
trace(1) 
 
while 1 do 
 
 
     if match(upper("<title>404 - Page Not Found</title>"),upper(TheWebPage)) then  
       TheWebPage = "404" 
       exit 
     end if 
      
     retry2 then end if 
       
end while 

Now is the syntax error obvious?

Just to restate, statements such as IF, WHILE, FOR etc are terminated by a two word combination, and those words do not have to be on the same line. The terminator is 'end' followed by 'if', while', 'for' etc that may or may not be on the same line.

4. Re: Isn't this wrong?

• Posted by CoJaBo Jul 25, 2010
• 1107 views

Ah, the dangling IF at 2 in the morning..
I've been there before o_O

The error when you use a reserved keyword really ought to be improved-
"a name is expected here" is patent nonsense, because it worked before and to the reader there is clearly a name there, even though newer versions of Eu think it is some other type of token.
How about having the interpreter state what it thinks is there, like PHP does?
"expected a name, not a RETRY statement", just printing out whatever type of token Eu thinks it has there.
That should inspire the user to think, hey, theres a retry statement now, I cant use that as a name anymore.

6. Re: Isn't this wrong?

• Posted by useless Jul 25, 2010
• 1073 views

<0025>:: 'retry' is a reserved word and cannot be used as an identifier name 

I guess you haveto balance the programmer having some knowledge of the language vs the size of the error reporting string table. Or the time of day, surplus of blood in the caffine stream, etc.. I had also spent a couple minutes trying to figure out why "$+" wasn't working for string concatenation. And i figured "end" was fine, where Eu was reading "end if" across multiple text lines.

I once added 8k of error diagnostics to a cpu with only 64k of address space, but i was able to page it out during runtime. Sometimes it's just worth it to hit a couple keys and instantly have the cheatsheet.

useless