caseless dictionary howto ?

[Stef Mientki]

hello,

I need to search a piece of text and make all words that are equal
(except their case) also equal in their case, based on the first occurrence.
So I'm using a dictionary to store names and attributes of objects.
As as I need to search on the caseless name (so I've choosen lowercase),
My dictionairy looks like this:

self.procs [ "serial_hw_read " ] = ( "Serial_HW_Read ", "F", "++", T)

Is this really a good solution,
or are there better ways ?

thanks,
Stef Mientki

[Evan Klitzke]

On 6/19/07, Stef Mientki <S.************ **@mailbox.kun. nlwrote:

hello,

I need to search a piece of text and make all words that are equal
(except their case) also equal in their case, based on the first occurrence.
So I'm using a dictionary to store names and attributes of objects.
As as I need to search on the caseless name (so I've choosen lowercase),
My dictionairy looks like this:

self.procs [ "serial_hw_read " ] = ( "Serial_HW_Read ", "F", "++", T)

Is this really a good solution,
or are there better ways ?

Since you want an almost dictionary, you should create a new class
that inherits from dict and overloads the methods that you want to
change.

--
Evan Klitzke <ev**@yelp.co m>

[Stef Mientki]

Evan Klitzke wrote:

On 6/19/07, Stef Mientki <S.************ **@mailbox.kun. nlwrote:

>hello,

I need to search a piece of text and make all words that are equal
(except their case) also equal in their case, based on the first
occurrence.
So I'm using a dictionary to store names and attributes of objects.
As as I need to search on the caseless name (so I've choosen lowercase),
My dictionairy looks like this:

self.procs [ "serial_hw_read " ] = ( "Serial_HW_Read ", "F", "++", T)

Is this really a good solution,
or are there better ways ?

Since you want an almost dictionary, you should create a new class
that inherits from dict and overloads the methods that you want to
change.

thanks,
but still one question.

Suppose I succeed in creating my own type, derived from dictionary,
I would be able to add/set a key like this:

self.procs [ "Serial_HW_Read " ] = ( "F", "++", T)

and now I can query the dictionary by

self.procs.has_ key ( "serial_hw_read ")

but how do I get the original string "Serial_HW_Read " back ?

thanks,
Stef Mientki

[Steven Bethard]

Stef Mientki wrote:

Evan Klitzke wrote:

>On 6/19/07, Stef Mientki <S.************ **@mailbox.kun. nlwrote:

>>hello,

I need to search a piece of text and make all words that are equal
(except their case) also equal in their case, based on the first
occurrence.
So I'm using a dictionary to store names and attributes of objects.
As as I need to search on the caseless name (so I've choosen lowercase),
My dictionairy looks like this:

self.procs [ "serial_hw_read " ] = ( "Serial_HW_Read ", "F",
"++", T)

Is this really a good solution,
or are there better ways ?

Since you want an almost dictionary, you should create a new class
that inherits from dict and overloads the methods that you want to
change.

Suppose I succeed in creating my own type, derived from dictionary,
I would be able to add/set a key like this:

self.procs [ "Serial_HW_Read " ] = ( "F", "++", T)

and now I can query the dictionary by

self.procs.has_ key ( "serial_hw_read ")

but how do I get the original string "Serial_HW_Read " back ?

I probably wouldn't inherit from dict -- you're going to need to
redefine most of the methods anyway. I'd do something like::

>>class D(object):

.... def __init__(self):
.... self._dict = {}
.... self._original_ keys = {}
.... def __iter__(self):
.... for key in self._dict:
.... yield self._original_ keys[key]
.... def __contains__(se lf, key):
.... return key.lower() in self._dict
.... def __getitem__(sel f, key):
.... return self._dict[key.lower()]
.... def __setitem__(sel f, key, value):
.... self._dict[key.lower()] = value
.... if key not in self._original_ keys:
.... self._original_ keys[key.lower()] = key
....

>>procs = D()
procs['Serial_HW_Read '] = 'F', '++', 'T'
'serial_hw_re ad' in procs

True

>>procs['SErial_Hw_reAD ']

('F', '++', 'T')

>>list(procs)

['Serial_HW_Read ']

Note that because I store the first form encountered for every key, I
can always use the lower-case version to retrieve the "original string".

STeVe

[Gabriel Genellina]

En Tue, 19 Jun 2007 19:40:10 -0300, Steven Bethard
<st************ @gmail.comescri bió:

Stef Mientki wrote:

>Evan Klitzke wrote:

>>On 6/19/07, Stef Mientki <S.************ **@mailbox.kun. nlwrote:

I need to search a piece of text and make all words that are equal
(except their case) also equal in their case, based on the first
occurrence .

... def __setitem__(sel f, key, value):
... self._dict[key.lower()] = value
... if key not in self._original_ keys:
... self._original_ keys[key.lower()] = key
...

Note that because I store the first form encountered for every key, I
can always use the lower-case version to retrieve the "original string".

As written, it stores the last used spelling; a small change is required
to get the intended behavior:

... def __setitem__(sel f, key, value):
... self._dict[key.lower()] = value
... if key.lower() not in self._original_ keys:
... self._original_ keys[key.lower()] = key

--
Gabriel Genellina

[Steven Bethard]

Gabriel Genellina wrote:

En Tue, 19 Jun 2007 19:40:10 -0300, Steven Bethard
<st************ @gmail.comescri bió:

>Stef Mientki wrote:

>>Evan Klitzke wrote:
On 6/19/07, Stef Mientki <S.************ **@mailbox.kun. nlwrote:
>
I need to search a piece of text and make all words that are equal
(except their case) also equal in their case, based on the first
occurrenc e.

>... def __setitem__(sel f, key, value):
... self._dict[key.lower()] = value
... if key not in self._original_ keys:
... self._original_ keys[key.lower()] = key
...

Note that because I store the first form encountered for every key, I
can always use the lower-case version to retrieve the "original string".

As written, it stores the last used spelling; a small change is required
to get the intended behavior:

>... def __setitem__(sel f, key, value):
... self._dict[key.lower()] = value
... if key.lower() not in self._original_ keys:
... self._original_ keys[key.lower()] = key

Good catch. Thanks!

Steve

[stef]

Gabriel Genellina wrote:

En Tue, 19 Jun 2007 19:40:10 -0300, Steven Bethard
<st************ @gmail.comescri bió:

>Stef Mientki wrote:

>>Evan Klitzke wrote:
On 6/19/07, Stef Mientki <S.************ **@mailbox.kun. nlwrote:
>
I need to search a piece of text and make all words that are equal
(except their case) also equal in their case, based on the first
occurrenc e.

>... def __setitem__(sel f, key, value):
... self._dict[key.lower()] = value
... if key not in self._original_ keys:
... self._original_ keys[key.lower()] = key
...

Note that because I store the first form encountered for every key, I
can always use the lower-case version to retrieve the "original string".

As written, it stores the last used spelling; a small change is
required to get the intended behavior:

>... def __setitem__(sel f, key, value):
... self._dict[key.lower()] = value
... if key.lower() not in self._original_ keys:
... self._original_ keys[key.lower()] = key

--Gabriel Genellina

thanks guys,
I'll think a while which solution I'll choose.

cheers,
Stef Mientki

[Stefan Behnel]

Stef Mientki wrote:

I need to search a piece of text and make all words that are equal
(except their case) also equal in their case, based on the first
occurrence.
So I'm using a dictionary to store names and attributes of objects.
As as I need to search on the caseless name (so I've choosen lowercase),
My dictionairy looks like this:

self.procs [ "serial_hw_read " ] = ( "Serial_HW_Read ", "F", "++", T)

I have no idea what the "F", "++", "T" means at the end (if it's some kind of
flags or attributes, maybe a class to hold them would look better), but that's
a good solution to the problem IMHO.

Stefan

[stef]

Stefan Behnel wrote:

Stef Mientki wrote:

>I need to search a piece of text and make all words that are equal
(except their case) also equal in their case, based on the first
occurrence.
So I'm using a dictionary to store names and attributes of objects.
As as I need to search on the caseless name (so I've choosen lowercase),
My dictionairy looks like this:

self.procs [ "serial_hw_read " ] = ( "Serial_HW_Read ", "F", "++", T)

I have no idea what the "F", "++", "T" means at the end (if it's some kind of
flags or attributes,

This makes part of a simulation of a JAL (a Pascal like language for
micros),
and this dictionary builds up the namespace,
used in translation JAL to pure Python.

Serial_HW_Read = the name of a function
"F" = the type of that function (procedure / function / pseudo variable
/ interrupt /..)
"++" = the direction of each parameters, (input / output / input+output )
T = a tupple, containing the type of each of the parameters (bit / byte/
sbyte / word / ...)

maybe a class to hold them would look better),

maybe, but no human is looking at it ;-)

but that's
a good solution to the problem IMHO.

Seeing the other solution,
I indeed tend to stick to this solution,
because it's the most simple one
(certainly if you realize that the dictionary is generated by the
program itself)

cheers,
Stef Mientki

Stefan

[Carsten Haese]

On Wed, 2007-06-20 at 11:14 +0200, stef wrote:

Stefan Behnel wrote:
Serial_HW_Read = the name of a function
"F" = the type of that function (procedure / function / pseudo variable
/ interrupt /..)
"++" = the direction of each parameters, (input / output / input+output )
T = a tupple, containing the type of each of the parameters (bit / byte/
sbyte / word / ...)

maybe a class to hold them would look better),

maybe, but no human is looking at it ;-)

But humans might look at the code that looks at the thing.
thing.func_type is self-documenting, thing[0] is not.

--
Carsten Haese
http://informixdb.sourceforge.net