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Very basic question about Flex
From: |
address@hidden |
Subject: |
Very basic question about Flex |
Date: |
Fri, 22 Feb 2019 15:00:51 +0100 |
User-agent: |
Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.5.1 |
Hi everyone,
i've started to read the lex and yacc book and the bison and flex book.
now in the first example they have the following code:
%{
/**
* First example program for flex
*
*/
%}
%%
is |
am |
are |
where |
was |
be |
being |
been |
do |
does |
did |
should |
can |
could |
has |
have |
had |
go { printf("%s is a verb\n", yytext); }
[a-zA-Z]+ { printf("%s is not a verb", yytext); }
.|\n { ECHO; /* normal default anyway */ }
%%
int main(int argc, char **argv)
{
yylex();
}
Now my question is when i enter one of the verbs it's working normaly
like expected, but when i enter for example 234someword i also get the
messsage %s is not a verb but i've no rule saying that, i've only
[a-zA-Z]+ to catch this situation, why does he also react on word that
begin with a number ??
best regards!
- Very basic question about Flex,
address@hidden <=