3r33800.  3r33818. 3r3r6806. 3r33800.  3r33818.

Replacing the "slices" slices on the ranks ranges

 3r33818.
 3r33818. 3r3804. Python 3r3807.  3r33818. 3r3804. 11l 3r3807.  3r33818. 3r3809.  3r33818.
 3r33818. 3r3804. 3r3667. 3r3658. s[-1]3r33818. s[-2]3r33818. s[:-1]3r33818. s[1:]3r33818. s[:1:]3r33818. s[1:2]3r33818. s[::2]3r33818. s[3:10:2]3r33818. s[3:10:]3r33818. 3r3673.
 3r33818. 3r3804. 3r3667. 3r3658. s.last
s[(len)-2]3r33818. s[0<(len)-1]3r33818. s[1]3r33818. s[0<1]3r33818. s[1<2]3r33818. s[(0).step(2)]3r33818. s[(3<10).step(2)]3r33818. s[3<10]3r33818. 3r3673.
 3r33818. 3r3809.  3r33818. 3r33811. Explicit indication for indexing from the end of the array s[(len)-2]3r3673. instead of just 3r3638. s[-2]3r3673. needed to eliminate the following errors: 3r30000.  3r33818.  3r33818. When you want for example to get the previous character on 3r3638. s[i-1]3r3673. , but if i = ? this /this record instead of an error will silently return the last character of the string [и я на практике сталкивался с такой ошибкой — коммит]3r3772. .  3r33818. Expression 3r3638. s[i:]3r3673. after 3r3638. i = s.find (":") will work incorrectly when the character is not found in line [вместо ‘‘часть строки начиная с первого символа : и далее’’ будет взят последний символ строки]3r3772. (and generally, return 3r3633. -1 function 3r3638. find () 3r3672. In Python, I consider it also wrong 3r3771.[следует возвращать null/None [а если требуется -1, то следует писать явно: i = s.find(":") ?? -1]3rr77772. 3r3771.  3r33818. Record 3r3638. s[-n:]3r3673. for 3r3638. n the last characters of the string will not work correctly when n = 0.  3r33818. 3r33800.  3r33818.

Chains of comparison operators

3r33800.  3r33818. At first glance, it’s an outstanding feature of the Python language, but in practice it can easily be discarded /dispensed with by the operator 3r3638. in and ranges: 3r30000.  3r33818.

1.  3r33818.
2. 3r337. 3r33737. In all places where I met Python's list comprehension, you can easily get away with the functions `filter ()` and `map ()`. 3r33712. 3r33737. 3r3667. 3r3658. dirs[:]=[d for d in dirs if d[0]! = '.' and d! = exclude_dir]
   dirs[:]= filter (lambda d: d[0]! = '.' and d! = exclude_dir, dirs)
   3r33818. '[' + ', '.join(python_types_to_11l[ty]for ty in self.type_args) + ']'
   '[' + ', '.join(map(lambda ty: python_types_to_11l[ty], self.type_args)) + ']'
   3r33818. # Nested list comprehension:
   matrix =[
   [1, 2, 3, 4], 3r33818.[5, 6, 7, 8], 3r33818.[9, 10, 11, 12], 3r33818. ]3r33818.[[row[i]for row in matrix]for i in range (4)]
   list (map (lambda i: list (map (lambda row: row[i], matrix)), range (4)))
   3r3673. 3r33838. 3r33838.  3r33818.
3. 3r337. 3r33737. `filter ()` and `map ()` in 11l look prettier than in Python [/b] 3r33737. 3r3667. 3r3668. dirs[:]= filter (lambda d: d[0]! = '.' and d! = exclude_dir, dirs)
   dirs = dirs.filter (d -> d[0]! = ‘.’ & d! = @ exclude_dir)
   3r33818. '[' + ', '.join(map(lambda ty: python_types_to_11l[ty], self.type_args)) + ']'
   ‘W2w2w241. ) .join (‘,’)) ‘]’ 3r3-3818. 3r33818. outfile.write ("n" .join (x[1]for x in fileslist if x[0]))
   outfile.write ("n" .join (map (lambda x: x[1], filter (lambda x: x[0], fileslist))))
   outfile.write (fileslist.filter (x -> x[0]) .map (x -> x[1]) .join ("n"))
   3r3673. 3r33838. 3r33838. and therefore the need for list comprehensions in 11l actually disappears [замена list comprehension на filter() и/или map() выполняется в процессе преобразования Python-кода в 11l автоматически]3r3772. .  3r33818.

3r33800.  3r33818.

Convert the if-elif-else chain to switch

3r33800.  3r33818. While Python does not contain a switch statement, this is one of the most beautiful constructions in the 11l language, and so I decided to insert the switch automatically:
 3r33818. с точки зрения производительности]3r3772. but it is very convenient. 3r33800.  3r33818. 3r33800.  3r33818. In 11l, the same line corresponding to this line is 3r3771.[и полученная транспайлером Python → 11l]3r3772. Record not only comfortable [впрочем, не настолько изящная как в Python]3r3772. , but also fast:
 3r33818. 3r3667. 3r3668. var tag = switch prev_char () {‘*’ {‘b’}; ‘_’ {‘U’}; ‘-’ {‘s’}; ‘~’ {‘I’}} 3-333818. 3r3673. 3r33800.  3r33818. The above line is shipped to: 3r30000.  3r33818. 3r3667. 3r3668. auto tag =[&](const auto & a) {return a == u '*'? u'b'_C: a == u'_ '? u'u'_C: a == u'- '? u's'_C: a == u '~'? u'i'_C: throw KeyError (a);} (prev_char ()); 3r33818. 3r3673. [Вызов лямбда-функции компилятор C++ встроитinline в процессе оптимизации и останется только цепочка операторов ?/:.]3r3772. 3r33800.  3r33818. 3r33800.  3r33818. In the case when assignment is made to a variable, the dictionary is left as it is: 3r30000.  3r33818.

Capture Ca pture of external variables [/h3] 3r33800.  3r33818. In Python, to indicate that a variable is not local, but must be taken outside [от текущей функции]3r3772. , the keyword nonlocal is used.[в противном случае к примеру found = True будет трактоваться как создание новой локальной переменной found, а не присваивание значения уже существующей внешней переменной]3r3772. . 3r33800.  3r33818. In 11l, the prefix @: 3r33800 is used for this.  3r33818.

[посредством ключевого слова global]3r3772. , then you get an inconspicuous bug:
 3r33818. [справа]3r3772. unlike python [слева]3r3772. will generate an error at compile time ‘undeclared variable break_label_index ’. 3r33800.  3r33818. 3r33800.  3r33818.

The index /number of the current item in the

container. 3r33800.  3r33818. I always forget the order of the variables that the Python function returns enumerate {first comes the value, and then the index or vice versa}. Similar behavior in Ruby - 3r3638. each.with_index - it is much easier to remember: with index means that index comes after value, and not before. But in 11l, the logic is even easier to remember: 3r30000.  3r33818.
 3r33818.
 3r33818. 3r3804. Python 3r3807.  3r33818. 3r3804. 11l 3r3807.  3r33818. 3r3809.  3r33818.
 3r33818. 3r3804. 3r3667. 3r3658. items =['A', 'B', 'C']3r33818. for index, item in enumerate (items):
print (str (index) + '=' + item)
3r3673.
 3r33818. 3r3804. 3r3667. 3r3668. var items =[‘A’, ‘B’, ‘C’]3r33818. loop (item) items
print (loop.index ‘=’ item)
3r3673.
 3r33818. 3r3809.  3r33818. 3r33811. 3r33800.  3r33818.
Performance 3r38282. 3r33800.  3r33818. As a test used
a program for converting pc markup to HTML [/leech] , and the source data is taken source articles on pc markup
[так как эта статья на данный момент — самая большая из написанных на пк-разметке]3r3772. , and repeated 10 times, that is, a 488 KB file is obtained from a 48.8 kilobyte article. 3r33800.  3r33818. 3r33800.  3r33818. Here is a diagram showing how many times the corresponding method of executing Python code is faster than the original implementation of 3r3771.[CPython]3r3772. : 3r33800.  3r33818. 3r33737. 3r33714. 3r33800.  3r33818. Run time 3r3771.[время преобразования файла размером 488Кб]3r3772. was 868 ms for CPython and 38 ms for the generated C ++ code
[это время включает в себя полноценный [т.е. не просто работу Shed Skin but it does not support local functions. 3r33800.  3r33818. Numba also failed (yields an error ‘Use of unknown opcode LOAD_BUILD_CLASS’). 3r33800.  3r33818. 3r33737. Here is the archive 3r3806. with the program used to compare performance 3r3771.[под Windows]3r3772. (Requires installed Python 3.6 or higher and the following Python packages: pywin3? cython). 3r33800.  3r33818. 3r33838. 3r33838. 3r33800.  3r33818. Python source and output of Python transpilers → 11l and 11l → C ++:
 3r33818.
 3r33818.
 3r33818. 3r3804. Python
 3r33818. 3r3804. Generated 11l 3r33800.  3r33818. (with keywords instead of letters)
 3r33818. 3r3804. 11l 3r3806. 3r33800.  3r33818. (with letters)
 3r33818. 3r3804. 3r3805. Generated C ++
 3r33818. 3r3809.  3r33818. 3r33811. 3r33838. 3r33818. 3r33818. 3r33818. 3r33816. ! function (e) {function t (t, n) {if (! (n in e)) {for (var, a = e.document, i = a.scripts, o = i.length; o-- ;) if (-1! == i[o].src.indexOf (t)) {r = i[o]; break} if (! r) {r = a.createElement ("script"), r.type = "text /jаvascript", r.async =! ? r.defer =! ? r.src = t, r.charset = "UTF-8"; var d = function () {var e = a.getElementsByTagName ("script")[0]; e.parentNode.insertBefore (r, e)}; "[object Opera]" == e.opera? a.addEventListener? a.addEventListener ("DOMContentLoaded", d ): d ()}}} t ("//mediator.mail.ru/script/2820404/"""_mediator") () (); 3r33817. 3r33818. 3r33838.