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how to test for a ' in an if condition

I am reading a file with read/lines e.g    
myLines: read/lines %file1.txt
for each line myLines [ test if the first character is ' ]
    
in the file there are lines that start with ' and some without.
    
e.g of lines in the file:-
' insert something into table '
commit;
    
how do I test that the first character is a ' ?
    
I cannot get the syntax right.
    
I tried :-    
if line/1 = ''' but got error.
if line/1 = #''' but gets error.
    
what is the correct syntax to use?

posted by:   change last text       10-Dec-2016/22:39:05-8:00



You can use the pound symbol, or convert the character to a string:
    
write %firstcharquote.txt {'adfs'^/qwer^/'uiop}
x: read/lines %firstcharquote.txt
foreach line x [
    if line/1 = #"'" [
     print rejoin ["Single quote starts: " line]
    ]
]
    
x: read/lines %firstcharquote.txt
foreach line x [
    if (form line/1) = "'" [
     print rejoin ["Single quote starts: " line]
    ]
]
    
halt

posted by:   Nick       11-Dec-2016/0:00:01-8:00



Thanks Nick.
    
sorry there was a typo it is " (double quote sign)    
    
I thought I typed (double quote sign)


posted by:   change last text       11-Dec-2016/8:22:48-8:00



It works the same for double quotes:
    
R E B O L []
    
write %firstcharquote.txt {"adfs"^/qwer^/"uiop}
    
x: read/lines %firstcharquote.txt
foreach line x [
    if line/1 = #"^"" [
     print rejoin ["Double quote starts: " line]
    ]
]
    
x: read/lines %firstcharquote.txt
foreach line x [
    if (form line/1) = {"} [
     print rejoin ["Double quote starts: " line]
    ]
]
    
halt
    
    
You can get the character code for any key using this script:
    
insert-event-func func [f e] [if e/type = 'key [print mold e/key] e]
view layout [text "Type keys to see their character/keycode"]

posted by:   Nick       11-Dec-2016/9:09:08-8:00



thanks Nick. it works.
    
thanks also for hte script to get the character code for any key. very useful to have this. I will keep it safely in my toolbox.

posted by:   change last text       11-Dec-2016/9:45:59-8:00



Take a look through http://re-bol.com/examples.txt
    
I put most of my useful code examples over the years in there (most of it's also at http://business-programming.com, with explanations ;)

posted by:   Nick       11-Dec-2016/19:15:42-8:00



thanks Nick.
    
I went through the examples, they are very helpful, and straight to the point, exactly what i am looking for.
    
thanks again.

posted by:   change last text       12-Dec-2016/21:19:19-8:00