Paul Garner anentropic

Introduction

I was recently asked to explain why I felt disappointed by Haskell, as a language. And, well. Crucified for crucified, I might as well criticise Haskell publicly.

First though, I need to make it explicit that I claim no particular skill with the language - I will in fact vehemently (and convincingly!) argue that I'm a terrible Haskell programmer. And what I'm about to explain is not meant as The Truth, but my current understanding, potentially flawed, incomplete, or flat out incorrect. I welcome any attempt at proving me wrong, because when I dislike something that so many clever people worship, it's usually because I missed an important detail.

Another important point is that this is not meant to convey the idea that Haskell is a bad language. I do feel, however, that the vocal, and sometimes aggressive, reverence in which it's held might lead people to have unreasonable expectations. It certainly was my case, and the reason I'm writing this.

Type classes

I love the concept of type class

	use serde::{Deserialize, Serialize};
	use serde_yaml::Value;
	use std::ffi::{CStr, CString};
	use std::os::raw::c_char;

	#[repr(C)]
	pub struct KeyValue {
	pub key: *const c_char,
	pub value: *const c_char,
	}

	"""
	A simply SublimeText plugin to run a command if matches a selector.

	Usage example - my `Default (OSX).sublime-mousemap`:
	[
	// for Python we use Anaconda's goto command, for go we use go_guru,
	// for others we use built-in goto command
	{ "button": "button1", "modifiers": ["ctrl"], "command": "mousemap_wrap",
	"press_command": "drag_select", "args": { "commands": [
	{


	type ('ty,'v) t =
	\| Nil : ('v, 'v) t
	\| Cons : 'a * ('ty, 'v) t -> ('a -> 'ty, 'v) t

	let cons x l = Cons (x,l)

	let plus1 l = Cons ((),l)

	let one x = Cons (x,Nil)

	import six
	from rest_framework import serializers, exceptions, parsers


	class PullSerializerMixin(object):
	pull_model = None

	def __init__(self, args, *kwargs):
	self.pull_model = kwargs.pop('pull_model', self.pull_model)
	super(PullSerializerMixin, self).__init__(args, *kwargs)

	from toolz import concat

	def page_iterator(query, page_size=999, **kwargs):
	'''
	Returns an iterator over pages of a query.
	Can be used to work-around the 1000 entity limit in remote_api_shell

	:params query: The query we're using.
	:params page_size: The page size to return.
	:params qwargs: Additional options for fetch_page

	>>> import sys
	>>> sys.path.append('/usr/local/google_appengine/')
	>>> from dev_appserver import fix_sys_path
	>>> fix_sys_path()
	>>> from google.appengine.api.croninfo import GrocValidator
	>>> GrocValidator().Validate('invalidsyntax')
	Traceback (most recent call last):
	File "<input>", line 1, in <module>
	File "/Applications/GoogleAppEngineLauncher.app/Contents/Resources/GoogleAppEngine-default.bundle/Contents/Resources/google_appengine/google/appengine/api/croninfo.py", li
	ne 78, in Validate

	-- show running queries (pre 9.2)
	SELECT procpid, age(clock_timestamp(), query_start), usename, current_query
	FROM pg_stat_activity
	WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%'
	ORDER BY query_start desc;

	-- show running queries (9.2)
	SELECT pid, age(clock_timestamp(), query_start), usename, query
	FROM pg_stat_activity
	WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%'

	#!/usr/bin/env bash
	# file: ~/.virtualenvs/postmkvirtualenv

	# This hook is run after a new virtualenv is activated.

	# setup python interpretor and sitepackages
	# for Sublime Text's SublimeCodeIntel plugin.
	# codeintel looks in the root of any folder opened via `subl foldername`
	# for foldername/.codeintel/config
	# it also looks in ~/.codeintel/config

	#! /bin/sh
	echo "Purging pyc files and empty directories..."

	# Start from the repository root.
	cd ./$(git rev-parse --show-cdup)

	# Delete .pyc files and empty directories.
	find . -name "*.pyc" -delete > /dev/null 2>&1 &
	find . -type d -empty -delete > /dev/null 2>&1 &