Add make_diagram.py to examples to demonstrate creating railroad diags for selected examples

1 files changed, 34 insertions, 0 deletions

diff --git a/examples/make_diagram.py b/examples/make_diagram.py
new file mode 100644
index 0000000..f1de4bf
--- /dev/null
+++ b/examples/make_diagram.py
@@ -0,0 +1,34 @@
+#
+# make_diagram.py
+#
+# Sample railroad diagrams of selected pyparsing examples.
+#
+# Copyright 2020, Paul McGuire
+
+from pyparsing.diagram import to_railroad, railroad_to_html
+
+
+def make_diagram(expr):
+    with open("output.html", "w", encoding="utf-8") as fp:
+        railroad = to_railroad(expr)
+        fp.write(railroad_to_html(railroad))
+
+
+# Uncomment the related import statement, and pass the imported parser to make_diagram
+
+# from examples.delta_time import time_expression
+# from examples.sexpParser import sexp
+# from examples.ebnftest import ebnf_parser
+# from examples.jsonParser import jsonObject
+# from examples.lucene_grammar import expression
+# from examples.invRegex import parser
+# from examples.oc import program
+# from examples.mozillaCalendarParser import calendars
+# from examples.pgn import pgnGrammar
+# from examples.idlParse import CORBA_IDL_BNF
+# from examples.chemicalFormulas import formula
+# from examples.romanNumerals import romanNumeral
+# from examples.protobuf_parser import parser
+from examples.parsePythonValue import listItem
+
+make_diagram(listItem)