fixes #261

Author: jph00

fastcore/_nbdev.py

@@ -159,6 +159,7 @@
          "Path.mk_write": "03_xtras.ipynb",
          "Path.ls": "03_xtras.ipynb",
          "Path.__repr__": "03_xtras.ipynb",
+         "truncstr": "03_xtras.ipynb",
          "spark_chars": "03_xtras.ipynb",
          "sparkline": "03_xtras.ipynb",
          "autostart": "03_xtras.ipynb",

fastcore/xtras.py

@@ -2,9 +2,9 @@
 
 __all__ = ['dict2obj', 'obj2dict', 'repr_dict', 'is_listy', 'shufflish', 'mapped', 'IterLen', 'ReindexCollection',
            'maybe_open', 'image_size', 'bunzip', 'join_path_file', 'loads', 'untar_dir', 'repo_details', 'run',
-           'open_file', 'save_pickle', 'load_pickle', 'spark_chars', 'sparkline', 'autostart', 'time_events',
-           'stringfmt_names', 'PartialFormatter', 'partial_format', 'utc2local', 'local2utc', 'trace', 'round_multiple',
-           'modified_env', 'ContextManagers', 'str2bool', 'sort_by_run']
+           'open_file', 'save_pickle', 'load_pickle', 'truncstr', 'spark_chars', 'sparkline', 'autostart',
+           'time_events', 'stringfmt_names', 'PartialFormatter', 'partial_format', 'utc2local', 'local2utc', 'trace',
+           'round_multiple', 'modified_env', 'ContextManagers', 'str2bool', 'sort_by_run']
 
 # Cell
 from .imports import *
@@ -221,6 +221,11 @@ def __repr__(self:Path):
         except: pass
     return f"Path({self.as_posix()!r})"
 
+# Cell
+def truncstr(s:str, maxlen:int, suf:str='…')->str:
+    "Truncate `s` to length `maxlen`, adding suffix `suf` if truncated"
+    return s[:maxlen-len(suf)]+suf if len(s)>maxlen else s
+
 # Cell
 spark_chars = '▁▂▃▅▆▇'
 

nbs/03_xtras.ipynb

@@ -618,7 +618,7 @@
     {
      "data": {
       "text/plain": [
-       "['e', 'a', 'c', 'h', 'g', 'b', 'f', 'd']"
+       "['d', 'c', 'h', 'a', 'b', 'g', 'e', 'f']"
       ]
      },
      "execution_count": null,
@@ -1319,6 +1319,31 @@
     "## Other Helpers"
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "#export\n",
+    "def truncstr(s:str, maxlen:int, suf:str='…')->str:\n",
+    "    \"Truncate `s` to length `maxlen`, adding suffix `suf` if truncated\"\n",
+    "    return s[:maxlen-len(suf)]+suf if len(s)>maxlen else s"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "w = 'abacadabra'\n",
+    "test_eq(truncstr(w, 15), w)\n",
+    "test_eq(truncstr(w, 5), 'abac…')\n",
+    "test_eq(truncstr(w, 5, suf=''), 'abaca')\n",
+    "test_eq(truncstr(w, 5, suf='!!'), 'aba!!')"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,