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-rw-r--r--tests/yacc_error5.py91
1 files changed, 91 insertions, 0 deletions
diff --git a/tests/yacc_error5.py b/tests/yacc_error5.py
new file mode 100644
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--- /dev/null
+++ b/tests/yacc_error5.py
@@ -0,0 +1,91 @@
+# -----------------------------------------------------------------------------
+# yacc_error5.py
+#
+# Lineno and position tracking with error tokens
+# -----------------------------------------------------------------------------
+import ply.yacc as yacc
+
+from calclex import tokens
+
+# Parsing rules
+precedence = (
+ ('left','PLUS','MINUS'),
+ ('left','TIMES','DIVIDE'),
+ ('right','UMINUS'),
+ )
+
+# dictionary of names
+names = { }
+
+def p_statement_assign(t):
+ 'statement : NAME EQUALS expression'
+ names[t[1]] = t[3]
+
+def p_statement_assign_error(t):
+ 'statement : NAME EQUALS error'
+ line_start, line_end = t.linespan(3)
+ pos_start, pos_end = t.lexspan(3)
+ print("Assignment Error at %d:%d to %d:%d" % (line_start,pos_start,line_end,pos_end))
+
+def p_statement_expr(t):
+ 'statement : expression'
+ print(t[1])
+
+def p_expression_binop(t):
+ '''expression : expression PLUS expression
+ | expression MINUS expression
+ | expression TIMES expression
+ | expression DIVIDE expression'''
+ if t[2] == '+' : t[0] = t[1] + t[3]
+ elif t[2] == '-': t[0] = t[1] - t[3]
+ elif t[2] == '*': t[0] = t[1] * t[3]
+ elif t[2] == '/': t[0] = t[1] / t[3]
+
+def p_expression_uminus(t):
+ 'expression : MINUS expression %prec UMINUS'
+ t[0] = -t[2]
+
+def p_expression_group(t):
+ 'expression : LPAREN expression RPAREN'
+ line_start, line_end = t.linespan(2)
+ pos_start, pos_end = t.lexspan(2)
+ print("Group at %d:%d to %d:%d" % (line_start,pos_start, line_end, pos_end))
+ t[0] = t[2]
+
+def p_expression_group_error(t):
+ 'expression : LPAREN error RPAREN'
+ line_start, line_end = t.linespan(2)
+ pos_start, pos_end = t.lexspan(2)
+ print("Syntax error at %d:%d to %d:%d" % (line_start,pos_start, line_end, pos_end))
+ t[0] = 0
+
+def p_expression_number(t):
+ 'expression : NUMBER'
+ t[0] = t[1]
+
+def p_expression_name(t):
+ 'expression : NAME'
+ try:
+ t[0] = names[t[1]]
+ except LookupError:
+ print("Undefined name '%s'" % t[1])
+ t[0] = 0
+
+def p_error(t):
+ print("Syntax error at '%s'" % t.value)
+
+parser = yacc.yacc()
+import calclex
+calclex.lexer.lineno=1
+parser.parse("""
+a = 3 +
+(4*5) +
+(a b c) +
++ 6 + 7
+""", tracking=True)
+
+
+
+
+
+