I've gotten lost in an edge case of sorts. I'm working on a conversion of some old plaintext documentation to reST/Sphinx format, with the intent of outputting to a few formats (including HTML and text) from there. Some of the documented functions are for dealing with bitstrings, and a common case within these is a sentence like the following: Starting character is the blank " " which has the value 0.
I tried writing this as an inline literal the following ways: Starting character is the blank `` `` which has the value 0. or Starting character is the blank :literal:` ` which has the value 0. but there are a few problems with how these end up working:
reST syntax objects to a whitespace immediately inside of the literal, and it doesn't get recognized.
The above can be "fixed"--it looks correct in the HTML () and plaintext (" ") output--with a non-breaking space character inside the literal, but technically this is a lie in our case, and if a user copied this character, they wouldn't be copying what they expect.
The space can be wrapped in regular quotes, which allows the literal to be properly recognized, and while the output in HTML is probably fine (" "), in plaintext it ends up double-quoted as "" "".
In both 2/3 above, if the literal falls on the wrap boundary, the plaintext writer (which uses textwrap) will gladly wrap inside the literal and trim the space because it's at the start/end of the line.
I feel like I'm missing something; is there a good way to handle this?
Try using the unicode character codes. If I understand your question, this should work.
Here is a "|space|" and a non-breaking space (|nbspc|)
.. |space| unicode:: U+0020 .. space
.. |nbspc| unicode:: U+00A0 .. non-breaking space
You should see:
Here is a “ ” and a non-breaking space ( )
I was hoping to get out of this without needing custom code to handle it, but, alas, I haven't found a way to do so. I'll wait a few more days before I accept this answer in case someone has a better idea. The code below isn't complete, nor am I sure it's "done" (will sort out exactly what it should look like during our review process) but the basics are intact.
There are two main components to the approach:
introduce a char role which expects the unicode name of a character as its argument, and which produces an inline description of the character while wrapping the character itself in an inline literal node.
modify the text-wrapper Sphinx uses so that it won't break at the space.
Here's the code:
class TextWrapperDeux(TextWrapper):
_wordsep_re = re.compile(
r'((?<!`)\s+(?!`)|' # whitespace not between backticks
r'(?<=\s)(?::[a-z-]+:)`\S+|' # interpreted text start
r'[^\s\w]*\w+[a-zA-Z]-(?=\w+[a-zA-Z])|' # hyphenated words
r'(?<=[\w\!\"\'\&\.\,\?])-{2,}(?=\w))') # em-dash
#property
def wordsep_re(self):
return self._wordsep_re
def char_role(name, rawtext, text, lineno, inliner, options={}, content=[]):
"""Describe a character given by unicode name.
e.g., :char:`SPACE` -> "char:` `(U+00020 SPACE)"
"""
try:
character = nodes.unicodedata.lookup(text)
except KeyError:
msg = inliner.reporter.error(
':char: argument %s must be valid unicode name at line %d' % (text, lineno))
prb = inliner.problematic(rawtext, rawtext, msg)
return [prb], [msg]
app = inliner.document.settings.env.app
describe_char = "(U+%05X %s)" % (ord(character), text)
char = nodes.inline("char:", "char:", nodes.literal(character, character))
char += nodes.inline(describe_char, describe_char)
return [char], []
def setup(app):
app.add_role('char', char_role)
The code above lacks some glue to actually force the use of the new TextWrapper, imports, etc. When a full version settles out I may try to find a meaningful way to republish it; if so I'll link it here.
Markup: Starting character is the :char:`SPACE` which has the value 0.
It'll produce plaintext output like this: Starting character is the char:` `(U+00020 SPACE) which has the value 0.
And HTML output like: Starting character is the <span>char:<code class="docutils literal"> </code><span>(U+00020 SPACE)</span></span> which has the value 0.
The HTML output ends up looking roughly like: Starting character is the char:(U+00020 SPACE) which has the value 0.
I have a string called indicators, that the original developer of this application used to store single characters to indicate certain components of a model. I need to change the 7th character in the string, which I tried to do with the following code:
indicators[6] = "R"
The problem, I discovered quickly, was that the string is not always 7 characters long. For example, I have one set of values with U 2, that I need to convert to U 2 R (adding an additional space after the 2). Is there an easy way to force character count with Ruby?
use String.ljust(integer, padstr=' ')
If integer is greater than the length of [the receiver], returns a new String of
length integer with [the return value] left justified and padded with padstr;
otherwise, returns [an unmodified version of the receiver].
indicators = indicators.ljust(7)
indicators[6] = "R"
TL;DR
I need some help making a regex that will match any commas in a string that are side by side with unlimited white space around them and between them. The commas and their surrounding white space cannot be within matching single quotes or double quotes. I then need to capture the non-whitespace values from around those commas and count how many of those commas there are.
The values captured from around the commas will become their own values in the final array, while the commas that were counted will become nil values that are added to the final array.
Explanation of the problem:
This is a pretty complex problem so any help is greatly appreciated. I'm adding functionality to a library I've been using for a while now. I have this string that contains an array
"['d,og,f:asdf,:hello,",,\",,alsee',,,'ho,la', "-123,4,5.3", true, :good, false,,, "gr\'\'\'true,\',\'ee\"n", ":::testme", true]"
I would like to split this string only around select commas so that I have an array containing the following values
'd,og,f:asdf,:hello,",,\",,alsee'
nil
nil
'ho,la'
"-123,4,5.3"
true
:good
false
nil
nil
"gr\'\'\'true,\',\'ee\"n"
":::testme"
true
Then nil values are coming from the side by side commas that are not contained in any string. I wrote the following regex to split the string above (I already got rid of the start and end brackets):
/(?<=(?:['\"]|false|true|^|,)),(?=(?:\s*(?:(?::[\w]+)|(?:(?::?(?:\"[\s\S]*\")|(?:'[\s\S]*'))|(?:false|true)))\s*(?:,|$)))/
This splits the string so I get these values:
(0) "'d,og,f:asdf,:hello,",,\",,alsee',,"
(1) "'ho,la'"
(2) " "-123,4,5.3""
(3) " true"
(4) " :good, false,,"
(5) " "gr\'\'\'true,\',\'ee\"n""
(6) " ":::testme""
(7) " true"
All the values are strings as can be seen by their surrounding double quotes. They will not all end up that way though. A true or false will be converted to a boolean. The values surrounded by internal quotes will end up as strings. Then a value preceded with a : will end up as a symbol.
There are problems with the values at index 0 and 4. Index 0 should be this:
(0.0) "'d,og,f:asdf,:hello,",,\",,alsee'"
(0.1) nil
(0.2) nil
As you can see, the two commas at the end are gone. They have become the two nil values you see above. Then the string starts at the first single quote and ends at the last single quote, signifying that this value in the array is a string.
Then index 4 (" :good, false,,") should be this:
(4.0) " :good"
(4.1) " false"
(4.2) nil
(4.3) nil
The two commas at the end have become nil. Then " false" is it's own value which will later be converted to a boolean, while " :good" is also it's own value and will later be converted to a symbol.
To fix the problem with index 4 I have all the values run through a second regex. Here it is:
/^(\s*:(?:(?:[\w]+|\"[\s\S]+\"|'[\s\S]+')\s*)),([\s\S]*)$/
Instead of splitting this one I get the capture groups. It ends up returning this array for the value at index 4:
(4.0) " :good"
(4.1) " false,,"
That's what I wanted except for one problem. The value at index 4.1 (" false,,") has the two trailing commas which should be nil values in the array.
I need some help making a regex that will match any commas in a string that are side by side with unlimited white space around them and between them. The commas and their surrounding white space cannot be within matching single quotes or double quotes. I then need to capture the non-whitespace values from around those commas and count how many of those commas there are.
The values captured from around the commas will become their own values in the final array, while the commas that were counted will become nil values that are added to the final array.
"['d,og,f:asdf,:hello,"
,,\
",,alsee',,,'ho,la', "
-123,4,5.3
", true, :good, false,,, "
gr\
'\'
I count 4 strings. 3 in double quotes and the last one in single quotes?
You say this is broken down into smaller strings by your regx. But what about the characters outside the 4 strings?
Sorry, it looks a bit of a mess.
Try putting it all in a here document string and then breaking it down by a regx.
I finally figured it out myself. You can see how it fits in with the rest if you look at the description of the question above.
/^(([\s]*,)*)[\s]*((?::[\w]+)|(?::?(?:\"[\s\S]*\")|(?:'[\s\S]*')|false|true))?(([\s]*,)*)$/
string = 'xabcdexfghijk'
In the example above, 'x' appears twice. I want to capture everything between the first 'x' and the next 'x'. Thus, the desired result is a new string that equals 'xabcdex'. Any ideas?
You could use a simple regular expression: /x.*?x/. This basically means "match any characters in between two x characters, as few times as possible (non-greedy)".
The matched text can be extracted with String#[regexp]
string = 'xabcdexfghijk'
string[/x.*?x/] # => "xabcdex"
I am trying to display a double so it will always have 4 digits after the decimal point. For example, one double would be 0.0182, and another 0.0180. However, my problem occurs when the double ends in 0, which results in truncating the zero and leaving 0.018. I'm trying to add on a zero at the end of my number to fix this, but receiving a syntax error.
Dim minFeature As Double
...
minFeature = Round(minFeature, 4) ' keep only 4 digits of precision. works.
minFeature = CDbl(CStr(minFeature).PadRight(1, "0")) ' add on an extra 0. does not work.
This will return the number as a string and preserve four decimal places.
Format(minFeature, "0.0000")
For more information, see the docs on Format().