From 27e183a78c8062ed7c2bbb91655a5e56cd697bba Mon Sep 17 00:00:00 2001
From: Cengiz Kaygusuz <cngkaygusuz@gmail.com>
Date: Mon, 20 Nov 2017 20:46:39 -0500
Subject: Move src to root

---
 examples/scanExamples.py | 75 ++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 75 insertions(+)
 create mode 100644 examples/scanExamples.py

(limited to 'examples/scanExamples.py')

diff --git a/examples/scanExamples.py b/examples/scanExamples.py
new file mode 100644
index 0000000..24ae0e7
--- /dev/null
+++ b/examples/scanExamples.py
@@ -0,0 +1,75 @@
+#
+# scanExamples.py
+#
+#  Illustration of using pyparsing's scanString,transformString, and searchString methods
+#
+# Copyright (c) 2004, 2006 Paul McGuire
+#
+from pyparsing import Word, alphas, alphanums, Literal, restOfLine, OneOrMore, \
+    empty, Suppress, replaceWith
+
+# simulate some C++ code
+testData = """
+#define MAX_LOCS=100
+#define USERNAME = "floyd"
+#define PASSWORD = "swordfish"
+
+a = MAX_LOCS;
+CORBA::initORB("xyzzy", USERNAME, PASSWORD );
+
+"""
+
+#################
+print("Example of an extractor")
+print("----------------------")
+
+# simple grammar to match #define's
+ident = Word(alphas, alphanums+"_")
+macroDef = Literal("#define") + ident.setResultsName("name") + "=" + restOfLine.setResultsName("value")
+for t,s,e in macroDef.scanString( testData ):
+    print(t.name,":", t.value)
+    
+# or a quick way to make a dictionary of the names and values 
+# (return only key and value tokens, and construct dict from key-value pairs)
+# - empty ahead of restOfLine advances past leading whitespace, does implicit lstrip during parsing
+macroDef = Suppress("#define") + ident + Suppress("=") + empty + restOfLine
+macros = dict(list(macroDef.searchString(testData)))
+print("macros =", macros)
+print()
+
+
+#################
+print("Examples of a transformer")
+print("----------------------")
+
+# convert C++ namespaces to mangled C-compatible names
+scopedIdent = ident + OneOrMore( Literal("::").suppress() + ident )
+scopedIdent.setParseAction(lambda t: "_".join(t))
+
+print("(replace namespace-scoped names with C-compatible names)")
+print(scopedIdent.transformString( testData ))
+    
+    
+# or a crude pre-processor (use parse actions to replace matching text)
+def substituteMacro(s,l,t):
+    if t[0] in macros:
+        return macros[t[0]]
+ident.setParseAction( substituteMacro )
+ident.ignore(macroDef)
+
+print("(simulate #define pre-processor)")
+print(ident.transformString( testData ))
+
+
+
+#################
+print("Example of a stripper")
+print("----------------------")
+
+from pyparsing import dblQuotedString, LineStart
+
+# remove all string macro definitions (after extracting to a string resource table?)
+stringMacroDef = Literal("#define") + ident + "=" + dblQuotedString + LineStart()
+stringMacroDef.setParseAction( replaceWith("") )
+
+print(stringMacroDef.transformString( testData ))
-- 
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