diff options
| -rw-r--r-- | Doc/lib/libitertools.tex | 23 |
1 files changed, 11 insertions, 12 deletions
diff --git a/Doc/lib/libitertools.tex b/Doc/lib/libitertools.tex index 1ae4e96..5c6c2b7 100644 --- a/Doc/lib/libitertools.tex +++ b/Doc/lib/libitertools.tex @@ -18,14 +18,14 @@ avoid the readability and reliability problems which arise when many different individuals create their own slightly varying implementations, each with their own quirks and naming conventions. -The tools are designed to combine readily with each another. This makes +The tools are designed to combine readily with one another. This makes it easy to construct more specialized tools succinctly and efficiently in pure Python. -For instance, SML provides a tabulation tool: \code{tabulate(\var{f})} +For instance, SML provides a tabulation tool: \code{tabulate(f)} which produces a sequence \code{f(0), f(1), ...}. This toolbox provides \function{imap()} and \function{count()} which can be combined -to form \code{imap(\var{f}, count())} and produce an equivalent result. +to form \code{imap(f, count())} and produce an equivalent result. Whether cast in pure python form or C code, tools that use iterators are more memory efficient (and faster) than their list based counterparts. @@ -75,10 +75,9 @@ by functions or loops that truncate the stream. \begin{verbatim} def count(n=0): - cnt = n while True: - yield cnt - cnt += 1 + yield n + n += 1 \end{verbatim} Note, \function{count()} does not check for overflow and will return @@ -208,16 +207,16 @@ by functions or loops that truncate the stream. \end{verbatim} \end{funcdesc} -\begin{funcdesc}{repeat}{obj} - Make an iterator that returns \var{obj} over and over again. +\begin{funcdesc}{repeat}{object} + Make an iterator that returns \var{object} over and over again. Used as argument to \function{imap()} for invariant parameters - to the called function. Also used with function{izip()} to create + to the called function. Also used with \function{izip()} to create an invariant part of a tuple record. Equivalent to: \begin{verbatim} - def repeat(x): + def repeat(object): while True: - yield x + yield object \end{verbatim} \end{funcdesc} @@ -226,7 +225,7 @@ by functions or loops that truncate the stream. obtained from the iterable. Used instead of \function{imap()} when argument parameters are already grouped in tuples from a single iterable (the data has been ``pre-zipped''). The difference between - \function{imap()} and \function{starmap} parallels the distinction + \function{imap()} and \function{starmap()} parallels the distinction between \code{function(a,b)} and \code{function(*c)}. Equivalent to: |