diff --git a/patacrep/songbook/__main__.py b/patacrep/songbook/__main__.py
index 5713b4a9..004f3e95 100644
--- a/patacrep/songbook/__main__.py
+++ b/patacrep/songbook/__main__.py
@@ -9,6 +9,7 @@ import textwrap
 import sys
 
 from patacrep.build import SongbookBuilder, DEFAULT_STEPS
+from patacrep.utils import yesno
 from patacrep import __version__
 from patacrep import errors
 import patacrep.encoding
@@ -37,6 +38,16 @@ class VerboseAction(argparse.Action):
     def __call__(self, *_args, **_kwargs):
         LOGGER.setLevel(logging.DEBUG)
 
+def yesno_type(string):
+    """Interpret argument as a "yes" or a "no".
+
+    Raise `argparse.ArgumentTypeError` if string cannot be analysed.
+    """
+    try:
+        return yesno(string)
+    except ValueError as error:
+        raise argparse.ArgumentTypeError(str(error))
+
 def argument_parser(args):
     """Parse arguments"""
     parser = argparse.ArgumentParser(
@@ -68,6 +79,15 @@ def argument_parser(args):
         """)
         )
 
+    parser.add_argument(
+        '--cache', '-c', nargs=1,
+        help=textwrap.dedent("""\
+                Enable song cache.
+        """),
+        type=yesno_type,
+        default=[True],
+        )
+
     parser.add_argument(
         '--steps', '-s', nargs=1, type=str,
         action=ParseStepsAction,
@@ -107,7 +127,7 @@ def main():
 
     options = argument_parser(sys.argv[1:])
 
-    songbook_path = options.book[0]
+    songbook_path = options.book[-1]
     if os.path.exists(songbook_path + ".sb") and not os.path.exists(songbook_path):
         songbook_path += ".sb"
 
@@ -147,6 +167,7 @@ def main():
     datadirs.append(os.path.dirname(os.path.abspath(songbook_path)))
 
     songbook['datadir'] = datadirs
+    songbook['_cache'] = options.cache[0]
 
     try:
         sb_builder = SongbookBuilder(songbook, basename)
diff --git a/patacrep/songs/__init__.py b/patacrep/songs/__init__.py
index 129c8045..a36c17bc 100644
--- a/patacrep/songs/__init__.py
+++ b/patacrep/songs/__init__.py
@@ -104,7 +104,7 @@ class Song:
         self.encoding = config["encoding"]
         self.config = config
 
-        if datadir:
+        if self.datadir and self.config['_cache']:
             # Only songs in datadirs are cached
             self._filehash = hashlib.md5(
                 open(self.fullpath, 'rb').read()
@@ -155,7 +155,7 @@ class Song:
 
     def _write_cache(self):
         """If relevant, write a dumbed down version of self to the cache."""
-        if self.datadir:
+        if self.datadir and self.config['_cache']:
             cached = {}
             for attribute in self.cached_attributes:
                 cached[attribute] = getattr(self, attribute)
diff --git a/patacrep/songs/convert/__main__.py b/patacrep/songs/convert/__main__.py
index 6b40dca4..2880cdab 100644
--- a/patacrep/songs/convert/__main__.py
+++ b/patacrep/songs/convert/__main__.py
@@ -7,24 +7,21 @@ import os
 import logging
 import sys
 
-from patacrep.build import DEFAULT_CONFIG
 from patacrep import files
+from patacrep.build import DEFAULT_CONFIG
+from patacrep.utils import yesno
 
 LOGGER = logging.getLogger(__name__)
 
 def __usage():
     return "python3 -m patacrep.songs.convert INPUTFORMAT OUTPUTFORMAT FILES"
 
-def yesno(prompt):
-    while True:
-        answer = input("{} [yn] ".format(prompt))
-        if answer.strip().lower() == "y":
-            return True
-        if answer.strip().lower() == "n":
-            return False
-
 def confirm(destname):
-    return yesno("File '{}' already exist. Overwrite?".format(destname))
+    while True
+        try:
+            return yesno(input("File '{}' already exist. Overwrite? [yn] ".format(destname)))
+        except ValueError:
+            continue
 
 if __name__ == "__main__":
     if len(sys.argv) < 4:
diff --git a/patacrep/utils.py b/patacrep/utils.py
index 6d9eab4c..998fe738 100644
--- a/patacrep/utils.py
+++ b/patacrep/utils.py
@@ -59,3 +59,19 @@ class DictOfDict(UserDict):
                 DictOfDict._update(left[key], right[key])
             else:
                 left[key] = right[key]
+
+def yesno(string):
+    """Interpret string argument as a boolean.
+
+    May raise `ValueError` if argument cannot be interpreted.
+    """
+    yes_strings = ["y", "yes", "true", "1"]
+    no_strings = ["n", "no", "false", "0"]
+    if string.lower() in yes_strings:
+        return True
+    if string.lower() in no_strings:
+        return False
+    raise ValueError("'{}' is supposed to be one of {}.".format(
+        string,
+        ", ".join(["'{}'".format(string) for string in yes_strings + no_strings]),
+        ))
diff --git a/test/test_compilation/test_compilation.py b/test/test_compilation/test_compilation.py
index 0444efa2..f2c6d09c 100644
--- a/test/test_compilation/test_compilation.py
+++ b/test/test_compilation/test_compilation.py
@@ -111,7 +111,7 @@ class FileTest(unittest.TestCase, metaclass=dynamic.DynamicTest):
     @staticmethod
     def compile_songbook(songbook, steps=None):
         """Compile songbook, and return the command return code."""
-        command = [sys.executable, '-m', 'patacrep.songbook', songbook]
+        command = [sys.executable, '-m', 'patacrep.songbook', '--cache=no', songbook, '-v']
         if steps:
             command.extend(['--steps', steps])