# HG changeset patch
# User Franz Glasner <fzglas.hg@dom66.de>
# Date 1625816449 -7200
# Node ID 4ee53f6fcac1764bfdec5604581b034036afafa6
# Parent  a72e2f36983aacc19c23efcddb356735ae56e828
Implement ".getfirstvar()" and ".getfirstvar_s()".

BUGS: Not tested yet and no documentation yet.

diff -r a72e2f36983a -r 4ee53f6fcac1 configmix/config.py
--- a/configmix/config.py	Fri Jul 09 08:58:57 2021 +0200
+++ b/configmix/config.py	Fri Jul 09 09:40:49 2021 +0200
@@ -120,6 +120,25 @@
             varnameparts = (varname,)
         return self.getvarl(*varnameparts, namespace=varns, default=default)
 
+    def getfirstvar(self, *varnames, **kwds):
+        """A variant of :meth:`~.getvar` that returns the first found variable
+        in the list of given variables in `varnames`.
+
+        """
+        default = kwds.pop("default", _MARKER)
+        for varname in varnames:
+            try:
+                varvalue = self.getvar(varname)
+            except KeyError:
+                pass
+            else:
+                return varvalue
+        if default is _MARKER:
+            raise KeyError(
+                "none of the given variables found: %r" % (varnames,))
+        else:
+            return default
+
     def getvarl_s(self, *names, **kwds):
         """Get a variable - including variables from other namespaces.
 
@@ -161,6 +180,25 @@
             else:
                 return default
 
+    def getfirstvar_s(self, *varnames, **kwds):
+        """A variant of :meth:`~.getvar_s` that returns the first found
+        variable in the list of given variables in `varnames`.
+
+        """
+        default = kwds.pop("default", _MARKER)
+        for varname in varnames:
+            try:
+                obj = self.getvar(varname)
+            except KeyError:
+                pass
+            else:
+                return self.substitute_variables_in_obj(obj)
+        if default is _MARKER:
+            raise KeyError(
+                "none of the given variables found: %r" % (varnames,))
+        else:
+            return default
+
     def getintvarl_s(self, *names, **kwds):
         """Get a (possibly substituted) variable and coerce text to a
         number.