DOC/MAINT: Update wording re: fname inputs.

Both loadtxt and genfromtxt can read from lists and generators
of strings. The genfromtxt docstring captures this, but
loadtxt was missing this info.

Minor updates to docstrings and exceptions to:
 - make the wording more accurate.
 - homogenize the docs/exception messages for
   loadtxt/genfromtxt.
 - Make a ValueError in loadtxt a TypeError instead,
   which is more accurate and aligns with genfromtxt.

1 files changed, 13 insertions, 10 deletions

diff --git a/numpy/lib/npyio.py b/numpy/lib/npyio.py
index d12482cb7..9581cc1d9 100644
--- a/numpy/lib/npyio.py
+++ b/numpy/lib/npyio.py
@@ -783,10 +783,11 @@ def loadtxt(fname, dtype=float, comments='#', delimiter=None,
 
     Parameters
     ----------
-    fname : file, str, or pathlib.Path
-        File, filename, or generator to read.  If the filename extension is
-        ``.gz`` or ``.bz2``, the file is first decompressed. Note that
-        generators should return byte strings.
+    fname : file, str, pathlib.Path, list of str, generator
+        File, filename, list, or generator to read.  If the filename
+        extension is ``.gz`` or ``.bz2``, the file is first decompressed. Note
+        that generators must return bytes or strings. The strings
+        in a list or produced by a generator are treated as lines.
     dtype : data-type, optional
         Data-type of the resulting array; default: float.  If this is a
         structured data-type, the resulting array will be 1-dimensional, and
@@ -1075,8 +1076,9 @@ def loadtxt(fname, dtype=float, comments='#', delimiter=None,
             fh = iter(fname)
             fencoding = getattr(fname, 'encoding', 'latin1')
     except TypeError as e:
-        raise ValueError(
-            'fname must be a string, file handle, or generator'
+        raise TypeError(
+            f"fname must be a string, filehandle, list of strings, "
+            f"or generator. Got {type(fname)} instead."
         ) from e
 
     # input may be a python2 io stream
@@ -1581,8 +1583,8 @@ def genfromtxt(fname, dtype=float, comments='#', delimiter=None,
     ----------
     fname : file, str, pathlib.Path, list of str, generator
         File, filename, list, or generator to read.  If the filename
-        extension is `.gz` or `.bz2`, the file is first decompressed. Note
-        that generators must return byte strings. The strings
+        extension is ``.gz`` or ``.bz2``, the file is first decompressed. Note
+        that generators must return bytes or strings. The strings
         in a list or produced by a generator are treated as lines.
     dtype : dtype, optional
         Data type of the resulting array.
@@ -1801,8 +1803,9 @@ def genfromtxt(fname, dtype=float, comments='#', delimiter=None,
         fhd = iter(fid)
     except TypeError as e:
         raise TypeError(
-            "fname must be a string, filehandle, list of strings, "
-            "or generator. Got %s instead." % type(fname)) from e
+            f"fname must be a string, filehandle, list of strings, "
+            f"or generator. Got {type(fname)} instead."
+        ) from e
 
     with fid_ctx:
         split_line = LineSplitter(delimiter=delimiter, comments=comments,