Wen Yi <chuxuec@xxxxxxxxxxx> writes: > I am a beginner who are interested in database,when I do my study on the lex and yacc,I write a example.l like this: > %% > .\|n ECHO > %% > and then I generate a lex.yy.c use lex > but when I compile this file,something wrong happend: > [beginnerc@bogon temp]$ flex '/home/beginnerc/work/temp/example.l' > [beginnerc@bogon temp]$ cc lex.yy.c -o first -ll > /home/beginnerc/work/temp/example.l: In function ¡®yylex¡¯: > lex.yy.c:619:28: error: expected ¡®;¡¯ before ¡®break¡¯ I'm too lazy to actually go and read the flex manual right now, but that error message suggests strongly that you need a semicolon: .\|n ECHO; This'd make sense since the action is supposed to be a C statement. The universal style in Postgres' flex files is to write braces around each action: .\|n { ECHO; } but I'm not sure that that's actually required, if your action is only one C statement. I suspect it's just making the action into a valid C compound block. regards, tom lane