ex 9

simplemod.py

@@ -0,0 +1,13 @@
+x = 42
+
+
+def foo():
+    print('x is', x)
+
+
+class Spam:
+    def yow(self):
+        print('Yow!')
+
+
+print('loaded simplemod')

stock.py

@@ -1,4 +1,4 @@
-from structure import Structure
+from structly import *
 
 
 class Stock(Structure):
@@ -21,6 +21,7 @@ class Stock(Structure):
 
 
 if __name__ == '__main__':
-    from reader import read_csv_as_instances
 
     portfolio = read_csv_as_instances('Data/portfolio.csv', Stock)
+    formatter = create_formatter('text')
+    print_table(portfolio, ['name', 'shares', 'price'], formatter)

structly/__init__.py

@@ -0,0 +1,9 @@
+from .reader import *
+from .structure import *
+from .tableformat import *
+
+__all__ = [
+    *structure.__all__,
+    *reader.__all__,
+    *tableformat.__all__
+]

structly/reader.py

@@ -2,6 +2,8 @@ import csv
 import logging
 from typing import Any, Callable, Iterable, Mapping, Optional, Sequence
 
+__all__ = ['read_csv_as_dicts', 'read_csv_as_instances']
+
 
 def convert_csv(
     lines: Iterable[str],
@@ -24,7 +26,8 @@ def convert_csv(
 
 
 def csv_as_dicts(
-    lines: Iterable[str], types: Sequence[type], headers: Optional[Sequence[str]] = None
+    lines: Iterable[str], types: Sequence[type],
+    headers: Optional[Sequence[str]] = None
 ) -> Sequence[Mapping[str, Any]]:
     """Parse CSV lines into a list of dictionaries."""
 

structly/structure.py

@@ -1,6 +1,8 @@
 from collections import ChainMap
 
-from validate import Validator, validated
+from .validate import Validator, validated
+
+__all__ = ['Structure']
 
 
 def validate_attributes(cls):

structly/tableformat/__init__.py

@@ -0,0 +1,3 @@
+from .formatter import create_formatter, print_table
+
+__all__ = ['create_formatter', 'print_table']

structly/tableformat/csv.py

@@ -0,0 +1,12 @@
+from .formatter import TableFormatter
+
+
+class CSVTableFormatter(TableFormatter):
+    def _printer(self, data):
+        print(",".join(str(value) for value in data))
+
+    def headings(self, headers):
+        return self._printer(headers)
+
+    def row(self, rowdata):
+        return self._printer(rowdata)

structly/tableformat/formatter.py

@@ -2,6 +2,13 @@ from abc import ABC, abstractmethod
 
 
 class TableFormatter(ABC):
+    _formats = {}
+
+    @classmethod
+    def __init_subclass__(cls):
+        name = cls.__module__.split('.')[-1]
+        TableFormatter._formats[name] = cls
+
     @abstractmethod
     def headings(self, headers):
         pass
@@ -11,44 +18,6 @@ class TableFormatter(ABC):
         pass
 
 
-class TextTableFormatter(TableFormatter):
-    def _printer(self, data):
-        print(*("{: >10}".format(value) for value in data))
-
-    def headings(self, headers):
-        self._printer(headers)
-        print(*("{:->10}".format("") for _ in headers))
-
-    def row(self, rowdata):
-        self._printer(rowdata)
-
-
-class CSVTableFormatter(TableFormatter):
-    def _printer(self, data):
-        print(",".join(str(value) for value in data))
-
-    def headings(self, headers):
-        return self._printer(headers)
-
-    def row(self, rowdata):
-        return self._printer(rowdata)
-
-
-class HTMLTableFormatter(TableFormatter):
-    def _cell(self, value, tag):
-        return f"<{tag}>{value}</{tag}>"
-
-    def _printer(self, data, tag):
-        line = f"<tr>{' '.join(self._cell(str(value), tag) for value in data)}</tr>"
-        print(line)
-
-    def headings(self, headers):
-        return self._printer(headers, "th")
-
-    def row(self, rowdata):
-        return self._printer(rowdata, "td")
-
-
 class ColumnFormatMixin:
     formats = []
 
@@ -63,16 +32,15 @@ class UpperHeadersMixin:
 
 
 def create_formatter(name, column_formats=None, upper_headers=False):
-    formatters = {
-        "text": TextTableFormatter,
-        "csv": CSVTableFormatter,
-        "html": HTMLTableFormatter,
-    }
-    formatter = formatters.get(name, None)
     if not name:
         raise ValueError(f'formatter named "{name}" not implemented')
-    if upper_headers:
+    if name not in TableFormatter._formats:
+        __import__(f'{__package__}.{name}')
+    formatter = TableFormatter._formats.get(name)
+    if not formatter:
+        raise RuntimeError(f'Unknown format {name}')
 
+    if upper_headers:
         class _UpperFormatter(UpperHeadersMixin, formatter):
             pass
 

structly/tableformat/html.py

@@ -0,0 +1,16 @@
+from .formatter import TableFormatter
+
+
+class HTMLTableFormatter(TableFormatter):
+    def _cell(self, value, tag):
+        return f"<{tag}>{value}</{tag}>"
+
+    def _printer(self, data, tag):
+        line = f"<tr>{' '.join(self._cell(str(value), tag) for value in data)}</tr>"
+        print(line)
+
+    def headings(self, headers):
+        return self._printer(headers, "th")
+
+    def row(self, rowdata):
+        return self._printer(rowdata, "td")

structly/tableformat/text.py

@@ -0,0 +1,13 @@
+from .formatter import TableFormatter
+
+
+class TextTableFormatter(TableFormatter):
+    def _printer(self, data):
+        print(*("{: >10}".format(value) for value in data))
+
+    def headings(self, headers):
+        self._printer(headers)
+        print(*("{:->10}".format("") for _ in headers))
+
+    def row(self, rowdata):
+        self._printer(rowdata)