Expression | Pragmatic functional programming for Python inspired by F | Functional Programming library

 by   cognitedata Python Version: 5.0.2 License: MIT

kandi X-RAY | Expression Summary

kandi X-RAY | Expression Summary

Expression is a Python library typically used in Programming Style, Functional Programming applications. Expression has no bugs, it has no vulnerabilities, it has a Permissive License and it has low support. However Expression build file is not available. You can install using 'pip install Expression' or download it from GitHub, PyPI.

Expression aims to be a solid, type-safe, pragmatic, and high performance library for frictionless and practical functional programming in Python 3.8+. By pragmatic we mean that the goal of the library is to use simple abstractions to enable you to do practical and productive functional programming in Python (instead of being a Monad tutorial). Python is a multi-paradigm programming language that also supports functional programming constructs such as functions, higher-order functions, lambdas, and in many ways favors composition over inheritance. Better Python with F#.

            kandi-support Support

              Expression has a low active ecosystem.
              It has 312 star(s) with 26 fork(s). There are 35 watchers for this library.
              There were 3 major release(s) in the last 6 months.
              There are 12 open issues and 22 have been closed. On average issues are closed in 41 days. There are 5 open pull requests and 0 closed requests.
              It has a neutral sentiment in the developer community.
              The latest version of Expression is 5.0.2

            kandi-Quality Quality

              Expression has no bugs reported.

            kandi-Security Security

              Expression has no vulnerabilities reported, and its dependent libraries have no vulnerabilities reported.

            kandi-License License

              Expression is licensed under the MIT License. This license is Permissive.
              Permissive licenses have the least restrictions, and you can use them in most projects.

            kandi-Reuse Reuse

              Expression releases are available to install and integrate.
              Deployable package is available in PyPI.
              Expression has no build file. You will be need to create the build yourself to build the component from source.
              Installation instructions, examples and code snippets are available.

            Top functions reviewed by kandi - BETA

            kandi has reviewed Expression and discovered the below as its top functions. This is intended to give you an instant insight into Expression implemented functionality, and help decide if they suit your requirements.
            • Rebalance a key - value pair .
            • Post a message to the server .
            • Applies a key to a map .
            • Wrap a function with num_args .
            • Combine two sequences .
            • Fold fold_back function .
            • Create a pipeline from a function .
            • Returns a function that applies the given function to the given list .
            • Decorator to catch an exception .
            • Creates a function that returns the elements that satisfy the given predicate .
            Get all kandi verified functions for this library.

            Expression Key Features

            No Key Features are available at this moment for Expression.

            Expression Examples and Code Snippets

            Parse a lambda expression .
            pythondot img1Lines of Code : 87dot img1License : Non-SPDX (Apache License 2.0)
            copy iconCopy
            def _parse_lambda(lam):
              """Returns the AST and source code of given lambda function.
                lam: types.LambdaType, Python function/method/class
                gast.AST, Text: the parsed AST node; the source code that was parsed to
            Returns a list of lines matching regular expression .
            pythondot img2Lines of Code : 51dot img2License : Non-SPDX (Apache License 2.0)
            copy iconCopy
            def regex_find(orig_screen_output, regex, font_attr):
              """Perform regex match in rich text lines.
              Produces a new RichTextLines object with font_attr_segs containing highlighted
              regex matches.
              Example use cases include:
              1) search for specif  
            Preprocess an input expression string .
            pythondot img3Lines of Code : 36dot img3License : Non-SPDX (Apache License 2.0)
            copy iconCopy
            def preprocess_input_exprs_arg_string(input_exprs_str, safe=True):
              """Parses input arg into dictionary that maps input key to python expression.
              Parses input string in the format of 'input_key=' into a
              dictionary that maps each input_key to it  
            any specific reason to specify the type of Exception?
            Pythondot img4Lines of Code : 42dot img4License : Strong Copyleft (CC BY-SA 4.0)
            copy iconCopy
            while True:
                    x = int(input("Enter x: "))
                    y = int(input("Enter y: "))
                    z = x / y
                except ZeroDivisionError:
                    print("Undefined. Zero division error.")
                except ValueError:
            Subtract 1 from each element in the list in Python
            Pythondot img5Lines of Code : 31dot img5License : Strong Copyleft (CC BY-SA 4.0)
            copy iconCopy
            A = [*map(lambda x: x - 1, A)]
            a = [5, 6, 7, 11]
            a = [*map(lambda x: x - 1, a)]
            [4, 5, 6, 10]
            A = [i - 1 for i in A]
            In [5]: %%tim
            sort first numbers before the space
            Pythondot img6Lines of Code : 15dot img6License : Strong Copyleft (CC BY-SA 4.0)
            copy iconCopy
            def gematria(word):
                # using a "generator expression"
                return sum(alphabet[char] for char in word)
            with open('input.txt', encoding='utf8') as f:
                  # A generator expression that stores a sorted tuple of 
                  # the calculation a
            How to design a regular expression that can safely capture various types of numbers?
            Pythondot img7Lines of Code : 6dot img7License : Strong Copyleft (CC BY-SA 4.0)
            copy iconCopy
            -?\d[\d .,]*\b
            -?\d[\d .,]*\b(?:\.? *(?:×|-) *-?\d[\d .,]*\b)*
            │            |   |            ||            |
            error when changing a Tkinter button command method
            Pythondot img8Lines of Code : 7dot img8License : Strong Copyleft (CC BY-SA 4.0)
            copy iconCopy
            canvas[x].create_window((20, 20), window=buttonFrame)
            def create_lambda(x):
                return lambda: comments(x + 10)
            copy iconCopy
            df = pd.DataFrame({"Col1": ["123-abc"] * 3 + ["12345-abcde"] * 3})
            df[["Col1", "Col2"]] = (
                .str.split("-", expand=True)
                .rename(columns={0: "C1", 1: "C2"})
                .assign(C2=lambda df: df["C2"].where(df["C1"].str.len(
            IP Range Help. Repeating Entries on Output file
            Pythondot img10Lines of Code : 17dot img10License : Strong Copyleft (CC BY-SA 4.0)
            copy iconCopy
            def ipRange(start_ip, end_ip):
               start = list(map(int, start_ip.split(".")))
               end = list(map(int, end_ip.split(".")))
               temp = start
               ip_range = set()
               while temp != end:
                  start[3] += 1
                  for i i

            Community Discussions


            How to print ggplot for multiple tables in this case?
            Asked 2021-Jun-15 at 22:10

            I have this code which prints multiple tables



            Answered 2021-Jun-15 at 20:59

            So, this is a good opportunity to use purrr::map. You are half way there by applying code to one dataframe.

            You can take the code that you have written above and put it into a function.



            Primary expression error when defining a vector with ternary operator
            Asked 2021-Jun-15 at 21:48

            I have a simple code where I try to define a vector as one of two initializer lists using a ternary operator:



            Answered 2021-Jun-15 at 21:48

            Because you can't have braces in that context. If you look at cppreference on list initialization, you see that the case inside a ternary operator isn't defined. So it can't be parsed correctly and you get the error you have.

            You'd have to use something like this :



            How to make substring optional Kotlin regex
            Asked 2021-Jun-15 at 21:32

            I am practicing regular expressions in Kotlin and trying to start with a multiline string. However, I am not receiving any matches. I feel like I am doing it right and can't figure out the problem.

            Test lines:



            Answered 2021-Jun-15 at 21:32


            What are the differences between GNU grep's basic/extended and PCRE (`-P`) regular expressions?
            Asked 2021-Jun-15 at 20:55

            GNU grep's basic (BRE) and extended (ERE) syntax is documented at and PCRE is summarized at man pcresyntax, but there is no explicit comparison. What are the differences between GNU grep's basic/extended and PCRE (-P) regular expressions?



            Answered 2021-Jun-15 at 20:55

            My research of the major syntax and functionality differences from

            Perl supports much more additional functionality:

            • "nongreedy {}" with syntax re{...}?
            • additional anchors and character types \A, \C, \d, \D, \G, \p, \P, \s, \S, \X. \Z, \z.
            • (?#comment)
            • shy grouping (?:re), shy grouping + modifiers (?modifiers:re)
            • lookahead and negative lookahead (?=re) and (?!re), lookbehind and negative lookbehind (?<=p) and (?
            • Atomic groups (?>re)
            • Conditional expression (?(cond)re)
            • ... and more, see man pcresyntax



            JLEX lexical generator error: unterminated string at the end of the line
            Asked 2021-Jun-15 at 20:46

            I am generating lexical analyzer with JLEX. I found a regular expression for string literal from this link and used it in .jflex file same of other expressions. but it gives me this error : unterminated string at the end of the line
            StringLiteral = \"(\\.|[^"\\])*\"

            can anyone help me please, thanks.



            Answered 2021-Jun-15 at 20:46

            The regular expression you copied is for (f)lex, which uses a slightly different syntax for regular expressions. In particular, (f)lex treats " as an ordinary character inside bracketed classes, so [^"\\] is a character class matching anything other than (^) a quotation mark (") or a backslash (\\).

            However, in JFlex, the " is a quoting character, whether outside or inside brackets. So the " in the character class is unterminated. Hence the error message.

            So you need to backslash-escape it:



            what is the best regular expression to replace non numeric character in a string preceded by certain phrase in python?
            Asked 2021-Jun-15 at 20:02

            I have to parse lists of names, addresses, etc. that were OCRed and have invalid/incorrect characters in them and on the state postal code I need to recognize the pattern with a 2 character state followed by a 5 digit postal code and replace any non numeric characters in the postal code. I might have OK 7-41.03 at the end of a string I need to remove the hyphen and period. I know that re.sub('[^0-9]+', '', '7-41.03') will remove the desired characters but I need it only replace characters in numbers when found at the end of the string and only if preceded by a two character state wrapped in spaces like OK. It seems if I add anything to the regular expression as far as a lookbehind expression then I can't seem to get the characters replaced. I've come up with the following but I think there must be a simpler expression to accomplish this. Example:



            Answered 2021-Jun-15 at 20:02

            You need to make use of re.sub callbacks:



            How to use a generic method to remove outliers only if they exist in R
            Asked 2021-Jun-15 at 19:58

            I am using a method to remove univariate outliers. This method only works if the vector contains outliers.

            How is it possible to generalize this method to work also with vectors without outliers. I tried with ifelse without success.



            Answered 2021-Jun-15 at 19:58

            Negate (!) instead of using - which would work even when there are no outliers



            Moq System.NotSupportedException
            Asked 2021-Jun-15 at 18:09

            I get it again and again



            Answered 2021-Jun-15 at 18:09

            You have to make the property overridable, so make it virtual:



            MVVM WPF - How to update DataGrid bound to ObservableCollection
            Asked 2021-Jun-15 at 17:35
            What I'm trying to do:

            I have a WPF app, linked to a SQL-server. I am using the MVVM-light package (I do actually have Prism.Core installed, but I'm not sure if I'm using it or not.... new to MVVM).

            There's a DataGrid, bound to an ObservableCollection. I have been trying to implement the PropertyChangedEventHandler, but I can't seem to get it to work.

            I have a Delete button bound, and I am able to remove rows, but when I re-open the form, the changes does not carry over.

            I tried to change the binding-mode for the DataGrid from OneWay to TwoWay. With OneWay, the changes does not carry over when I re-open the form. With TwoWay, I get this error message when opening the child form (which contains the DataGrid):

            System.InvalidOperationException: 'A TwoWay or OneWayToSource binding cannot work on the read->only property 'licenseHolders' of type 'Ridel.Hub.ViewModel.LicenseHoldersViewModel'.'

            So, If I then add a set; to my public ObservableCollection licenseHolders { get; }, the program runs, but the previous problem persists, like it did when there was a OneWay mode configuration on the DataGrid.

            What do I need to do to get this to work without communicating directly with the Sql-server, which would defy the whole point of using this methodology in the first place?

            ViewModel: ...


            Answered 2021-Jun-15 at 13:26

            You are confusing topics. The VM needs InotifyPropertyChanged events, which you have but are not using, to notify the Xaml in the front-end that a VMs property has changed and to bind to the new data reference.

            This is needed for Lists or ObservableCollections. Once that is done, the ObservableCollection will then send notifications on changes to the list as items are added or removed.

            Because you miss the first step:



            Spring JPA DTO projection and handling the nested projection with null values
            Asked 2021-Jun-15 at 17:31

            I am using class based projection with constructor expressions. here is a sample code form my work



            Answered 2021-Jun-15 at 00:02

            Community Discussions, Code Snippets contain sources that include Stack Exchange Network


            No vulnerabilities reported

            Install Expression

            You can install the latest expression from PyPI by running pip (or pip3). Note that expression only works for Python 3.8+.


            Expression will never provide you with all the features of F# and .NET. We are providing a few of the features we think are useful, and will add more on-demand as we go along.
            Find more information at:

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            pip install Expression

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            gh repo clone cognitedata/Expression

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