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-rw-r--r--ext/ply/example/BASIC/basiclex.py74
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diff --git a/ext/ply/example/BASIC/basiclex.py b/ext/ply/example/BASIC/basiclex.py
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+# An implementation of Dartmouth BASIC (1964)
+
+from ply import *
+
+keywords = (
+ 'LET','READ','DATA','PRINT','GOTO','IF','THEN','FOR','NEXT','TO','STEP',
+ 'END','STOP','DEF','GOSUB','DIM','REM','RETURN','RUN','LIST','NEW',
+)
+
+tokens = keywords + (
+ 'EQUALS','PLUS','MINUS','TIMES','DIVIDE','POWER',
+ 'LPAREN','RPAREN','LT','LE','GT','GE','NE',
+ 'COMMA','SEMI', 'INTEGER','FLOAT', 'STRING',
+ 'ID','NEWLINE'
+)
+
+t_ignore = ' \t'
+
+def t_REM(t):
+ r'REM .*'
+ return t
+
+def t_ID(t):
+ r'[A-Z][A-Z0-9]*'
+ if t.value in keywords:
+ t.type = t.value
+ return t
+
+t_EQUALS = r'='
+t_PLUS = r'\+'
+t_MINUS = r'-'
+t_TIMES = r'\*'
+t_POWER = r'\^'
+t_DIVIDE = r'/'
+t_LPAREN = r'\('
+t_RPAREN = r'\)'
+t_LT = r'<'
+t_LE = r'<='
+t_GT = r'>'
+t_GE = r'>='
+t_NE = r'<>'
+t_COMMA = r'\,'
+t_SEMI = r';'
+t_INTEGER = r'\d+'
+t_FLOAT = r'((\d*\.\d+)(E[\+-]?\d+)?|([1-9]\d*E[\+-]?\d+))'
+t_STRING = r'\".*?\"'
+
+def t_NEWLINE(t):
+ r'\n'
+ t.lexer.lineno += 1
+ return t
+
+def t_error(t):
+ print "Illegal character", t.value[0]
+ t.lexer.skip(1)
+
+lex.lex()
+
+
+
+
+
+
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+