lexer and parser for basic timed word strings

1 files changed, 62 insertions, 0 deletions

diff --git a/lib/lex.py b/lib/lex.py
new file mode 100644
index 0000000..c0323fa
--- /dev/null
+++ b/lib/lex.py
@@ -0,0 +1,62 @@
+from sly import Lexer, Parser
+
+
+class TimedWordLexer(Lexer):
+    tokens = {LPAREN, RPAREN, IDENTIFIER, NUMBER, ARGSEP, FUNCTIONSEP}
+    ignore = ' \t'
+
+    LPAREN = r'\('
+    RPAREN = r'\)'
+    IDENTIFIER = r'[a-zA-Z_][a-zA-Z0-9_]*'
+    NUMBER = r'[0-9e.]+'
+    ARGSEP = r','
+    FUNCTIONSEP = r';'
+
+
+class TimedWordParser(Parser):
+    tokens = TimedWordLexer.tokens
+
+    @_('timedSymbol FUNCTIONSEP timedWord')
+    def timedWord(self, p):
+        ret = [p.timedSymbol]
+        ret.extend(p.timedWord)
+        return ret
+
+    @_('timedSymbol FUNCTIONSEP', 'timedSymbol')
+    def timedWord(self, p):
+        return [p.timedSymbol]
+
+    @_('IDENTIFIER', 'IDENTIFIER LPAREN RPAREN')
+    def timedSymbol(self, p):
+        return (p.IDENTIFIER,)
+
+    @_('IDENTIFIER LPAREN args RPAREN')
+    def timedSymbol(self, p):
+        return (p.IDENTIFIER, *p.args)
+
+    @_('arg ARGSEP args')
+    def args(self, p):
+        ret = [p.arg]
+        ret.extend(p.args)
+        return ret
+
+    @_('arg')
+    def args(self, p):
+        return [p.arg]
+
+    @_('NUMBER')
+    def arg(self, p):
+        return [float(p.NUMBER)]
+
+    @_('IDENTIFIER')
+    def arg(self, p):
+        return [p.IDENTIFIER]
+
+
+if __name__ == '__main__':
+    data = 'init(); sleep(12345); foo(_, 7);'
+    lexer = TimedWordLexer()
+    parser = TimedWordParser()
+    for tok in lexer.tokenize(data):
+        print('type={}, value={}'.format(tok.type, tok.value))
+    print(parser.parse(lexer.tokenize(data)))