parse external files -- SOLVED

Gaspar Chilingarov <>
Fri Oct 28 11:44:13 CEST 2005


>> On 27 Oct 2005, at 23:25, Gaspar Chilingarov wrote:
>> Hi all!
>>
>> I need to have files in plaintext format, describing some forms  
>> functionality -
>> which i need to load, parse and generate html from them.
>>
>> files will look like this:
>>
>> {form, personalinfo,
>>     [ {firstname, string},
>>       {lastname, string},
>>       {submit, button}
>>     ],
>>     fun
>>       (List) -> validateForm(List)
>>     end
>> }
>>
>>
>> so, I need them parse info valid erlkang terms - tuples, lists,  funs, 
>> etc.
>> I understand , that such functionality already is in library :)  but , 
>> hm, I've
>> missed where )


 > Sean Hinde wrote:
> ()25> {ok, B, _}=erl_scan:string(A).
> {ok,[{'{',1},
>      {atom,1,form},
>      {',',1},
>      {atom,1,personalinfo},
>      {',',1},
>      {'[',2},
> etc...
> 
> ()28> erl_parse:parse_exprs(B ++ [{dot,1}]).
> {ok,[{tuple,1,
>             [{atom,1,form},
>              {atom,1,personalinfo},
>              {cons,2,
>                    {tuple,2,[{atom,2,firstname},{atom,2,string}]},
>                    {cons,3,
>                          {tuple,3,[{atom,3,lastname},{atom,3,string}]},
>                          {cons,4,{tuple,4,[{atom,4|...},{atom|...}]}, 
> {nil,5}}}},
>              {'fun',6,
>                     {clauses,[{clause,7,
>                                       [{var,7,'List'}],
>                                       [],
>                                       [{call,7,{atom|...}, [...]}]}]}}]}]}
> 

I should do one more step -- just call
erl_eval:exprs/2 on result, returned from erl_parse:parse_exprs

so whole code shoudl look like this -

toErlangStructure(Text) ->
     {ok, Tokens, _} = erl_scan:string(Text),
     {ok, ParsedForm} = erl_parse:parse_exprs(Tokens),
     Bindings = erl_eval:new_bindings(),
     {value, ErlangTerms, _NewBinding} = erl_eval:exprs(ParsedForm, 
Bindings),
     ErlangTerms.

some binding processign should be done, of course, but in general that's 
it :)

thanks all for replies.


-- 
Gaspar Chilingarov
System Administrator

t +37491 419763 (mob)
t +37410 240399 (office)
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