Repo re-org, make gerberex tests run

1 files changed, 0 insertions, 979 deletions

diff --git a/gerber/excellon_statements.py b/gerber/excellon_statements.py
deleted file mode 100644
index 2c50ef9..0000000
--- a/gerber/excellon_statements.py
+++ /dev/null
@@ -1,979 +0,0 @@
-#!/usr/bin/env python
-# -*- coding: utf-8 -*-
-
-# copyright 2014 Hamilton Kibbe <ham@hamiltonkib.be>
-#
-# Licensed under the Apache License, Version 2.0 (the "License");
-# you may not use this file except in compliance with the License.
-# You may obtain a copy of the License at
-
-#     http://www.apache.org/licenses/LICENSE-2.0
-
-# Unless required by applicable law or agreed to in writing, software
-# distributed under the License is distributed on an "AS IS" BASIS,
-# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-# See the License for the specific language governing permissions and
-# limitations under the License.
-"""
-Excellon Statements
-====================
-**Excellon file statement classes**
-
-"""
-
-import re
-import uuid
-import itertools
-from .utils import (parse_gerber_value, write_gerber_value, decimal_string,
-                    inch, metric)
-
-
-__all__ = ['ExcellonTool', 'ToolSelectionStmt', 'CoordinateStmt',
-           'CommentStmt', 'HeaderBeginStmt', 'HeaderEndStmt',
-           'RewindStopStmt', 'EndOfProgramStmt', 'UnitStmt',
-           'IncrementalModeStmt', 'VersionStmt', 'FormatStmt', 'LinkToolStmt',
-           'MeasuringModeStmt', 'RouteModeStmt', 'LinearModeStmt', 'DrillModeStmt',
-           'AbsoluteModeStmt', 'RepeatHoleStmt', 'UnknownStmt',
-           'ExcellonStatement', 'ZAxisRoutPositionStmt',
-           'RetractWithClampingStmt', 'RetractWithoutClampingStmt',
-           'CutterCompensationOffStmt', 'CutterCompensationLeftStmt',
-           'CutterCompensationRightStmt', 'ZAxisInfeedRateStmt',
-           'NextToolSelectionStmt', 'SlotStmt']
-
-
-class ExcellonStatement(object):
-    """ Excellon Statement abstract base class
-    """
-
-    @classmethod
-    def from_excellon(cls, line):
-        raise NotImplementedError('from_excellon must be implemented in a '
-                                  'subclass')
-
-    def __init__(self, unit='inch', id=None):
-        self.units = unit
-        self.id = uuid.uuid4().int if id is None else id
-
-    def to_excellon(self, settings=None):
-        raise NotImplementedError('to_excellon must be implemented in a '
-                                  'subclass')
-
-    def to_inch(self):
-        self.units = 'inch'
-
-    def to_metric(self):
-        self.units = 'metric'
-
-    def offset(self, x_offset=0, y_offset=0):
-        pass
-
-    def __eq__(self, other):
-        return self.__dict__ == other.__dict__
-
-
-class ExcellonTool(ExcellonStatement):
-    """ Excellon Tool class
-
-    Parameters
-    ----------
-    settings : FileSettings (dict-like)
-        File-wide settings.
-
-    kwargs : dict-like
-        Tool settings from the excellon statement. Valid keys are:
-            - `diameter` : Tool diameter [expressed in file units]
-            - `rpm` : Tool RPM
-            - `feed_rate` : Z-axis tool feed rate
-            - `retract_rate` : Z-axis tool retraction rate
-            - `max_hit_count` : Number of hits allowed before a tool change
-            - `depth_offset` : Offset of tool depth from tip of tool.
-
-    Attributes
-    ----------
-    number : integer
-        Tool number from the excellon file
-
-    diameter : float
-        Tool diameter in file units
-
-    rpm : float
-        Tool RPM
-
-    feed_rate : float
-        Tool Z-axis feed rate.
-
-    retract_rate : float
-        Tool Z-axis retract rate
-
-    depth_offset : float
-        Offset of depth measurement from tip of tool
-
-    max_hit_count : integer
-        Maximum number of tool hits allowed before a tool change
-
-    hit_count : integer
-        Number of tool hits in excellon file.
-    """
-
-    PLATED_UNKNOWN = None
-    PLATED_YES = 'plated'
-    PLATED_NO = 'nonplated'
-    PLATED_OPTIONAL = 'optional'
-
-    @classmethod
-    def from_tool(cls, tool):
-        args = {}
-
-        args['depth_offset'] = tool.depth_offset
-        args['diameter'] = tool.diameter
-        args['feed_rate'] = tool.feed_rate
-        args['max_hit_count'] = tool.max_hit_count
-        args['number'] = tool.number
-        args['plated'] = tool.plated
-        args['retract_rate'] = tool.retract_rate
-        args['rpm'] = tool.rpm
-
-        return cls(None, **args)
-
-    @classmethod
-    def from_excellon(cls, line, settings, id=None, plated=None):
-        """ Create a Tool from an excellon file tool definition line.
-
-        Parameters
-        ----------
-        line : string
-            Tool definition line from an excellon file.
-
-        settings : FileSettings (dict-like)
-            Excellon file-wide settings
-
-        Returns
-        -------
-        tool : Tool
-            An ExcellonTool representing the tool defined in `line`
-        """
-        commands = pairwise(re.split('([BCFHSTZ])', line)[1:])
-        args = {}
-        args['id'] = id
-        nformat = settings.format
-        zero_suppression = settings.zero_suppression
-        for cmd, val in commands:
-            if cmd == 'B':
-                args['retract_rate'] = parse_gerber_value(val, nformat, zero_suppression)
-            elif cmd == 'C':
-                args['diameter'] = parse_gerber_value(val, nformat, zero_suppression)
-            elif cmd == 'F':
-                args['feed_rate'] = parse_gerber_value(val, nformat, zero_suppression)
-            elif cmd == 'H':
-                args['max_hit_count'] = parse_gerber_value(val, nformat, zero_suppression)
-            elif cmd == 'S':
-                args['rpm'] = 1000 * parse_gerber_value(val, nformat, zero_suppression)
-            elif cmd == 'T':
-                args['number'] = int(val)
-            elif cmd == 'Z':
-                args['depth_offset'] = parse_gerber_value(val, nformat, zero_suppression)
-
-        if plated != ExcellonTool.PLATED_UNKNOWN:
-            # Sometimees we can can parse the plating status
-            args['plated'] = plated
-        return cls(settings, **args)
-
-    @classmethod
-    def from_dict(cls, settings, tool_dict):
-        """ Create an ExcellonTool from a dict.
-
-        Parameters
-        ----------
-        settings : FileSettings (dict-like)
-            Excellon File-wide settings
-
-        tool_dict : dict
-            Excellon tool parameters as a dict
-
-        Returns
-        -------
-        tool : ExcellonTool
-            An ExcellonTool initialized with the parameters in tool_dict.
-        """
-        return cls(settings, **tool_dict)
-
-    def __init__(self, settings, **kwargs):
-        if kwargs.get('id') is not None:
-            super(ExcellonTool, self).__init__(id=kwargs.get('id'))
-        self.settings = settings
-        self.number = kwargs.get('number')
-        self.feed_rate = kwargs.get('feed_rate')
-        self.retract_rate = kwargs.get('retract_rate')
-        self.rpm = kwargs.get('rpm')
-        self.diameter = kwargs.get('diameter')
-        self.max_hit_count = kwargs.get('max_hit_count')
-        self.depth_offset = kwargs.get('depth_offset')
-        self.plated = kwargs.get('plated')
-
-        self.hit_count = 0
-
-    def to_excellon(self, settings=None):
-        if self.settings and not settings:
-            settings = self.settings
-        fmt = settings.format
-        zs = settings.zero_suppression
-        stmt = 'T%02d' % self.number
-        if self.retract_rate is not None:
-            stmt += 'B%s' % write_gerber_value(self.retract_rate, fmt, zs)
-        if self.feed_rate is not None:
-            stmt += 'F%s' % write_gerber_value(self.feed_rate, fmt, zs)
-        if self.max_hit_count is not None:
-            stmt += 'H%s' % write_gerber_value(self.max_hit_count, fmt, zs)
-        if self.rpm is not None:
-            if self.rpm < 100000.:
-                stmt += 'S%s' % write_gerber_value(self.rpm / 1000., fmt, zs)
-            else:
-                stmt += 'S%g' % (self.rpm / 1000.)
-        if self.diameter is not None:
-            stmt += 'C%s' % decimal_string(self.diameter, fmt[1], True)
-        if self.depth_offset is not None:
-            stmt += 'Z%s' % write_gerber_value(self.depth_offset, fmt, zs)
-        return stmt
-
-    def to_inch(self):
-        if self.settings.units != 'inch':
-            self.settings.units = 'inch'
-            if self.diameter is not None:
-                self.diameter = inch(self.diameter)
-
-    def to_metric(self):
-        if self.settings.units != 'metric':
-            self.settings.units = 'metric'
-            if self.diameter is not None:
-                self.diameter = metric(self.diameter)
-
-    def _hit(self):
-        self.hit_count += 1
-
-    def equivalent(self, other):
-        """
-        Is the other tool equal to this, ignoring the tool number, and other file specified properties
-        """
-
-        if type(self) != type(other):
-            return False
-
-        return (self.diameter == other.diameter
-            and self.feed_rate == other.feed_rate
-            and self.retract_rate == other.retract_rate
-            and self.rpm == other.rpm
-            and self.depth_offset == other.depth_offset
-            and self.max_hit_count == other.max_hit_count
-            and self.plated == other.plated
-            and self.settings.units == other.settings.units)
-
-    def __repr__(self):
-        unit = 'in.' if self.settings.units == 'inch' else 'mm'
-        fmtstr = '<ExcellonTool %%02d: %%%d.%dg%%s dia.>' % self.settings.format
-        return fmtstr % (self.number, self.diameter, unit)
-
-
-class ToolSelectionStmt(ExcellonStatement):
-
-    @classmethod
-    def from_excellon(cls, line, **kwargs):
-        """ Create a ToolSelectionStmt from an excellon file line.
-
-        Parameters
-        ----------
-        line : string
-            Line from an Excellon file
-
-        Returns
-        -------
-        tool_statement : ToolSelectionStmt
-            ToolSelectionStmt representation of `line.`
-        """
-        line = line[1:]
-        compensation_index = None
-
-        # up to 3 characters for tool number (Frizting uses that)
-        if len(line) <= 3:
-            tool = int(line)
-        else:
-            tool = int(line[:2])
-            compensation_index = int(line[2:])
-
-        return cls(tool, compensation_index, **kwargs)
-
-    def __init__(self, tool, compensation_index=None, **kwargs):
-        super(ToolSelectionStmt, self).__init__(**kwargs)
-        tool = int(tool)
-        compensation_index = (int(compensation_index) if compensation_index
-                              is not None else None)
-        self.tool = tool
-        self.compensation_index = compensation_index
-
-    def to_excellon(self, settings=None):
-        stmt = 'T%02d' % self.tool
-        if self.compensation_index is not None:
-            stmt += '%02d' % self.compensation_index
-        return stmt
-
-class NextToolSelectionStmt(ExcellonStatement):
-
-    # TODO the statement exists outside of the context of the file,
-    # so it is imposible to know that it is really the next tool
-
-    def __init__(self, cur_tool, next_tool, **kwargs):
-        """
-        Select the next tool in the wheel.
-        Parameters
-        ----------
-        cur_tool : the tool that is currently selected
-        next_tool : the that that is now selected
-        """
-        super(NextToolSelectionStmt, self).__init__(**kwargs)
-
-        self.cur_tool = cur_tool
-        self.next_tool = next_tool
-
-    def to_excellon(self, settings=None):
-        stmt = 'M00'
-        return stmt
-
-class ZAxisInfeedRateStmt(ExcellonStatement):
-
-    @classmethod
-    def from_excellon(cls, line, **kwargs):
-        """ Create a ZAxisInfeedRate from an excellon file line.
-
-        Parameters
-        ----------
-        line : string
-            Line from an Excellon file
-
-        Returns
-        -------
-        z_axis_infeed_rate : ToolSelectionStmt
-            ToolSelectionStmt representation of `line.`
-        """
-        rate = int(line[1:])
-
-        return cls(rate, **kwargs)
-
-    def __init__(self, rate, **kwargs):
-        super(ZAxisInfeedRateStmt, self).__init__(**kwargs)
-        self.rate = rate
-
-    def to_excellon(self, settings=None):
-        return 'F%02d' % self.rate
-
-
-class CoordinateStmt(ExcellonStatement):
-
-    @classmethod
-    def from_point(cls, point, mode=None):
-
-        stmt = cls(point[0], point[1])
-        if mode:
-            stmt.mode = mode
-        return stmt
-
-    @classmethod
-    def from_excellon(cls, line, settings, **kwargs):
-        x_coord = None
-        y_coord = None
-        if line[0] == 'X':
-            splitline = line.strip('X').split('Y')
-            x_coord = parse_gerber_value(splitline[0], settings.format,
-                                         settings.zero_suppression)
-            if len(splitline) == 2:
-                y_coord = parse_gerber_value(splitline[1], settings.format,
-                                             settings.zero_suppression)
-        else:
-            y_coord = parse_gerber_value(line.strip(' Y'), settings.format,
-                                         settings.zero_suppression)
-        c = cls(x_coord, y_coord, **kwargs)
-        c.units = settings.units
-        return c
-
-    def __init__(self, x=None, y=None, **kwargs):
-        super(CoordinateStmt, self).__init__(**kwargs)
-        self.x = x
-        self.y = y
-        self.mode = None
-
-    def to_excellon(self, settings):
-        stmt = ''
-        if self.mode == "ROUT":
-            stmt += "G00"
-        if self.mode == "LINEAR":
-            stmt += "G01"
-        if self.x is not None:
-            stmt += 'X%s' % write_gerber_value(self.x, settings.format,
-                                               settings.zero_suppression)
-        if self.y is not None:
-            stmt += 'Y%s' % write_gerber_value(self.y, settings.format,
-                                               settings.zero_suppression)
-        return stmt
-
-    def to_inch(self):
-        if self.units == 'metric':
-            self.units = 'inch'
-            if self.x is not None:
-                self.x = inch(self.x)
-            if self.y is not None:
-                self.y = inch(self.y)
-
-    def to_metric(self):
-        if self.units == 'inch':
-            self.units = 'metric'
-            if self.x is not None:
-                self.x = metric(self.x)
-            if self.y is not None:
-                self.y = metric(self.y)
-
-    def offset(self, x_offset=0, y_offset=0):
-        if self.x is not None:
-            self.x += x_offset
-        if self.y is not None:
-            self.y += y_offset
-
-    def __str__(self):
-        coord_str = ''
-        if self.x is not None:
-            coord_str += 'X: %g ' % self.x
-        if self.y is not None:
-            coord_str += 'Y: %g ' % self.y
-
-        return '<Coordinate Statement: %s>' % coord_str
-
-
-class RepeatHoleStmt(ExcellonStatement):
-
-    @classmethod
-    def from_excellon(cls, line, settings, **kwargs):
-        match = re.compile(r'R(?P<rcount>[0-9]*)X?(?P<xdelta>[+\-]?\d*\.?\d*)?Y?'
-                           '(?P<ydelta>[+\-]?\d*\.?\d*)?').match(line)
-        stmt = match.groupdict()
-        count = int(stmt['rcount'])
-        xdelta = (parse_gerber_value(stmt['xdelta'], settings.format,
-                                     settings.zero_suppression)
-                  if stmt['xdelta'] is not '' else None)
-        ydelta = (parse_gerber_value(stmt['ydelta'], settings.format,
-                                     settings.zero_suppression)
-                  if stmt['ydelta'] is not '' else None)
-        c = cls(count, xdelta, ydelta, **kwargs)
-        c.units = settings.units
-        return c
-
-    def __init__(self, count, xdelta=0.0, ydelta=0.0, **kwargs):
-        super(RepeatHoleStmt, self).__init__(**kwargs)
-        self.count = count
-        self.xdelta = xdelta
-        self.ydelta = ydelta
-
-    def to_excellon(self, settings):
-        stmt = 'R%d' % self.count
-        if self.xdelta is not None and self.xdelta != 0.0:
-            stmt += 'X%s' % write_gerber_value(self.xdelta, settings.format,
-                                               settings.zero_suppression)
-        if self.ydelta is not None and self.ydelta != 0.0:
-            stmt += 'Y%s' % write_gerber_value(self.ydelta, settings.format,
-                                               settings.zero_suppression)
-        return stmt
-
-    def to_inch(self):
-        if self.units == 'metric':
-            self.units = 'inch'
-            if self.xdelta is not None:
-                self.xdelta = inch(self.xdelta)
-            if self.ydelta is not None:
-                self.ydelta = inch(self.ydelta)
-
-    def to_metric(self):
-        if self.units == 'inch':
-            self.units = 'metric'
-            if self.xdelta is not None:
-                self.xdelta = metric(self.xdelta)
-            if self.ydelta is not None:
-                self.ydelta = metric(self.ydelta)
-
-    def __str__(self):
-        return '<Repeat Hole: %d times, offset X: %g Y: %g>' % (
-            self.count,
-            self.xdelta if self.xdelta is not None else 0,
-            self.ydelta if self.ydelta is not None else 0)
-
-
-class CommentStmt(ExcellonStatement):
-
-    @classmethod
-    def from_excellon(cls, line, **kwargs):
-        return cls(line.lstrip(';'))
-
-    def __init__(self, comment, **kwargs):
-        super(CommentStmt, self).__init__(**kwargs)
-        self.comment = comment
-
-    def to_excellon(self, settings=None):
-        return ';%s' % self.comment
-
-
-class HeaderBeginStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(HeaderBeginStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return 'M48'
-
-
-class HeaderEndStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(HeaderEndStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return 'M95'
-
-
-class RewindStopStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(RewindStopStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return '%'
-
-
-class ZAxisRoutPositionStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(ZAxisRoutPositionStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return 'M15'
-
-
-class RetractWithClampingStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(RetractWithClampingStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return 'M16'
-
-
-class RetractWithoutClampingStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(RetractWithoutClampingStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return 'M17'
-
-
-class CutterCompensationOffStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(CutterCompensationOffStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return 'G40'
-
-
-class CutterCompensationLeftStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(CutterCompensationLeftStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return 'G41'
-
-
-class CutterCompensationRightStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(CutterCompensationRightStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return 'G42'
-
-
-class EndOfProgramStmt(ExcellonStatement):
-
-    @classmethod
-    def from_excellon(cls, line, settings, **kwargs):
-        match = re.compile(r'M30X?(?P<x>\d*\.?\d*)?Y?'
-                           '(?P<y>\d*\.?\d*)?').match(line)
-        stmt = match.groupdict()
-        x = (parse_gerber_value(stmt['x'], settings.format,
-                                settings.zero_suppression)
-             if stmt['x'] is not '' else None)
-        y = (parse_gerber_value(stmt['y'], settings.format,
-                                settings.zero_suppression)
-             if stmt['y'] is not '' else None)
-        c = cls(x, y, **kwargs)
-        c.units = settings.units
-        return c
-
-    def __init__(self, x=None, y=None, **kwargs):
-        super(EndOfProgramStmt, self).__init__(**kwargs)
-        self.x = x
-        self.y = y
-
-    def to_excellon(self, settings=None):
-        stmt = 'M30'
-        if self.x is not None:
-            stmt += 'X%s' % write_gerber_value(self.x)
-        if self.y is not None:
-            stmt += 'Y%s' % write_gerber_value(self.y)
-        return stmt
-
-    def to_inch(self):
-        if self.units == 'metric':
-            self.units = 'inch'
-            if self.x is not None:
-                self.x = inch(self.x)
-            if self.y is not None:
-                self.y = inch(self.y)
-
-    def to_metric(self):
-        if self.units == 'inch':
-            self.units = 'metric'
-            if self.x is not None:
-                self.x = metric(self.x)
-            if self.y is not None:
-                self.y = metric(self.y)
-
-    def offset(self, x_offset=0, y_offset=0):
-        if self.x is not None:
-            self.x += x_offset
-        if self.y is not None:
-            self.y += y_offset
-
-
-class UnitStmt(ExcellonStatement):
-
-    @classmethod
-    def from_settings(cls, settings):
-        """Create the unit statement from the FileSettings"""
-
-        return cls(settings.units, settings.zeros)
-
-    @classmethod
-    def from_excellon(cls, line, **kwargs):
-        units = 'inch' if 'INCH' in line else 'metric'
-        zeros = 'leading' if 'LZ' in line else 'trailing'
-        if '0000.00' in line:
-            format = (4, 2)
-        elif '000.000' in line:
-            format = (3, 3)
-        elif '00.0000' in line:
-            format = (2, 4)
-        else:
-            format = None
-        return cls(units, zeros, format, **kwargs)
-
-    def __init__(self, units='inch', zeros='leading', format=None, **kwargs):
-        super(UnitStmt, self).__init__(**kwargs)
-        self.units = units.lower()
-        self.zeros = zeros
-        self.format = format
-
-    def to_excellon(self, settings=None):
-        # TODO This won't export the invalid format statement if it exists
-        stmt = '%s,%s' % ('INCH' if self.units == 'inch' else 'METRIC',
-                          'LZ' if self.zeros == 'leading'
-                          else 'TZ')
-        return stmt
-
-    def to_inch(self):
-        self.units = 'inch'
-
-    def to_metric(self):
-        self.units = 'metric'
-
-
-class IncrementalModeStmt(ExcellonStatement):
-
-    @classmethod
-    def from_excellon(cls, line, **kwargs):
-        return cls('off', **kwargs) if 'OFF' in line else cls('on', **kwargs)
-
-    def __init__(self, mode='off', **kwargs):
-        super(IncrementalModeStmt, self).__init__(**kwargs)
-        if mode.lower() not in ['on', 'off']:
-            raise ValueError('Mode may be "on" or "off"')
-        self.mode = mode
-
-    def to_excellon(self, settings=None):
-        return 'ICI,%s' % ('OFF' if self.mode == 'off' else 'ON')
-
-
-class VersionStmt(ExcellonStatement):
-
-    @classmethod
-    def from_excellon(cls, line, **kwargs):
-        version = int(line.split(',')[1])
-        return cls(version, **kwargs)
-
-    def __init__(self, version=1, **kwargs):
-        super(VersionStmt, self).__init__(**kwargs)
-        version = int(version)
-        if version not in [1, 2]:
-            raise ValueError('Valid versions are  1 or 2')
-        self.version = version
-
-    def to_excellon(self, settings=None):
-        return 'VER,%d' % self.version
-
-
-class FormatStmt(ExcellonStatement):
-
-    @classmethod
-    def from_excellon(cls, line, **kwargs):
-        fmt = int(line.split(',')[1])
-        return cls(fmt, **kwargs)
-
-    def __init__(self, format=1, **kwargs):
-        super(FormatStmt, self).__init__(**kwargs)
-        format = int(format)
-        if format not in [1, 2]:
-            raise ValueError('Valid formats are 1 or 2')
-        self.format = format
-
-    def to_excellon(self, settings=None):
-        return 'FMAT,%d' % self.format
-
-    @property
-    def format_tuple(self):
-        return (self.format, 6 - self.format)
-
-
-class LinkToolStmt(ExcellonStatement):
-
-    @classmethod
-    def from_excellon(cls, line, **kwargs):
-        linked = [int(tool) for tool in line.split('/')]
-        return cls(linked, **kwargs)
-
-    def __init__(self, linked_tools, **kwargs):
-        super(LinkToolStmt, self).__init__(**kwargs)
-        self.linked_tools = [int(x) for x in linked_tools]
-
-    def to_excellon(self, settings=None):
-        return '/'.join([str(x) for x in self.linked_tools])
-
-
-class MeasuringModeStmt(ExcellonStatement):
-
-    @classmethod
-    def from_excellon(cls, line, **kwargs):
-        if not ('M71' in line or 'M72' in line):
-            raise ValueError('Not a measuring mode statement')
-        return cls('inch', **kwargs) if 'M72' in line else cls('metric', **kwargs)
-
-    def __init__(self, units='inch', **kwargs):
-        super(MeasuringModeStmt, self).__init__(**kwargs)
-        units = units.lower()
-        if units not in ['inch', 'metric']:
-            raise ValueError('units must be "inch" or "metric"')
-        self.units = units
-
-    def to_excellon(self, settings=None):
-        return 'M72' if self.units == 'inch' else 'M71'
-
-    def to_inch(self):
-        self.units = 'inch'
-
-    def to_metric(self):
-        self.units = 'metric'
-
-
-class RouteModeStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(RouteModeStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return 'G00'
-
-
-class LinearModeStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(LinearModeStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return 'G01'
-
-
-class DrillModeStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(DrillModeStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return 'G05'
-
-
-class AbsoluteModeStmt(ExcellonStatement):
-
-    def __init__(self, **kwargs):
-        super(AbsoluteModeStmt, self).__init__(**kwargs)
-
-    def to_excellon(self, settings=None):
-        return 'G90'
-
-
-class UnknownStmt(ExcellonStatement):
-
-    @classmethod
-    def from_excellon(cls, line, **kwargs):
-        return cls(line, **kwargs)
-
-    def __init__(self, stmt, **kwargs):
-        super(UnknownStmt, self).__init__(**kwargs)
-        self.stmt = stmt
-
-    def to_excellon(self, settings=None):
-        return self.stmt
-
-    def __str__(self):
-        return "<Unknown Statement: %s>" % self.stmt
-
-
-class SlotStmt(ExcellonStatement):
-    """
-    G85 statement.  Defines a slot created by multiple drills between two specified points.
-
-    Format is two coordinates, split by G85in the middle, for example, XnY0nG85XnYn
-    """
-
-    @classmethod
-    def from_points(cls, start, end):
-
-        return cls(start[0], start[1], end[0], end[1])
-
-    @classmethod
-    def from_excellon(cls, line, settings, **kwargs):
-        # Split the line based on the G85 separator
-        sub_coords = line.split('G85')
-        (x_start_coord, y_start_coord) = SlotStmt.parse_sub_coords(sub_coords[0], settings)
-        (x_end_coord, y_end_coord) = SlotStmt.parse_sub_coords(sub_coords[1], settings)
-
-        # Some files seem to specify only one of the coordinates
-        if x_end_coord == None:
-            x_end_coord = x_start_coord
-        if y_end_coord == None:
-            y_end_coord = y_start_coord
-
-        c = cls(x_start_coord, y_start_coord, x_end_coord, y_end_coord, **kwargs)
-        c.units = settings.units
-        return c
-
-    @staticmethod
-    def parse_sub_coords(line, settings):
-
-        x_coord = None
-        y_coord = None
-
-        if line[0] == 'X':
-            splitline = line.strip('X').split('Y')
-            x_coord = parse_gerber_value(splitline[0], settings.format,
-                                         settings.zero_suppression)
-            if len(splitline) == 2:
-                y_coord = parse_gerber_value(splitline[1], settings.format,
-                                             settings.zero_suppression)
-        else:
-            y_coord = parse_gerber_value(line.strip(' Y'), settings.format,
-                                         settings.zero_suppression)
-
-        return (x_coord, y_coord)
-
-
-    def __init__(self, x_start=None, y_start=None, x_end=None, y_end=None, **kwargs):
-        super(SlotStmt, self).__init__(**kwargs)
-        self.x_start = x_start
-        self.y_start = y_start
-        self.x_end = x_end
-        self.y_end = y_end
-        self.mode = None
-
-    def to_excellon(self, settings):
-        stmt = ''
-
-        if self.x_start is not None:
-            stmt += 'X%s' % write_gerber_value(self.x_start, settings.format,
-                                               settings.zero_suppression)
-        if self.y_start is not None:
-            stmt += 'Y%s' % write_gerber_value(self.y_start, settings.format,
-                                               settings.zero_suppression)
-
-        stmt += 'G85'
-
-        if self.x_end is not None:
-            stmt += 'X%s' % write_gerber_value(self.x_end, settings.format,
-                                               settings.zero_suppression)
-        if self.y_end is not None:
-            stmt += 'Y%s' % write_gerber_value(self.y_end, settings.format,
-                                               settings.zero_suppression)
-
-        return stmt
-
-    def to_inch(self):
-        if self.units == 'metric':
-            self.units = 'inch'
-            if self.x_start is not None:
-                self.x_start = inch(self.x_start)
-            if self.y_start is not None:
-                self.y_start = inch(self.y_start)
-            if self.x_end is not None:
-                self.x_end = inch(self.x_end)
-            if self.y_end is not None:
-                self.y_end = inch(self.y_end)
-
-    def to_metric(self):
-        if self.units == 'inch':
-            self.units = 'metric'
-            if self.x_start is not None:
-                self.x_start = metric(self.x_start)
-            if self.y_start is not None:
-                self.y_start = metric(self.y_start)
-            if self.x_end is not None:
-                self.x_end = metric(self.x_end)
-            if self.y_end is not None:
-                self.y_end = metric(self.y_end)
-
-    def offset(self, x_offset=0, y_offset=0):
-        if self.x_start is not None:
-            self.x_start += x_offset
-        if self.y_start is not None:
-            self.y_start += y_offset
-        if self.x_end is not None:
-            self.x_end += x_offset
-        if self.y_end is not None:
-            self.y_end += y_offset
-
-    def __str__(self):
-        start_str = ''
-        if self.x_start is not None:
-            start_str += 'X: %g ' % self.x_start
-        if self.y_start is not None:
-            start_str += 'Y: %g ' % self.y_start
-
-        end_str = ''
-        if self.x_end is not None:
-            end_str += 'X: %g ' % self.x_end
-        if self.y_end is not None:
-            end_str += 'Y: %g ' % self.y_end
-
-        return '<Slot Statement: %s to %s>' % (start_str, end_str)
-
-def pairwise(iterator):
-    """ Iterate over list taking two elements at a time.
-
-    e.g. [1, 2, 3, 4, 5, 6] ==> [(1, 2), (3, 4), (5, 6)]
-    """
-    a, b = itertools.tee(iterator)
-    itr = zip(itertools.islice(a, 0, None, 2), itertools.islice(b, 1, None, 2))
-    for elem in itr:
-        yield elem