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Diffstat (limited to 'pl/utils.lua')
-rw-r--r-- | pl/utils.lua | 476 |
1 files changed, 0 insertions, 476 deletions
diff --git a/pl/utils.lua b/pl/utils.lua deleted file mode 100644 index f933afb..0000000 --- a/pl/utils.lua +++ /dev/null @@ -1,476 +0,0 @@ ---- Generally useful routines. --- See @{01-introduction.md.Generally_useful_functions|the Guide}. --- @module pl.utils -local format,gsub,byte = string.format,string.gsub,string.byte -local compat = require 'pl.compat' -local clock = os.clock -local stdout = io.stdout -local append = table.insert -local unpack = rawget(_G,'unpack') or rawget(table,'unpack') - -local collisions = {} - -local utils = { - _VERSION = "1.3.2", - lua51 = compat.lua51, - setfenv = compat.setfenv, - getfenv = compat.getfenv, - load = compat.load, - execute = compat.execute, - dir_separator = _G.package.config:sub(1,1), - unpack = unpack -} - ---- end this program gracefully. --- @param code The exit code or a message to be printed --- @param ... extra arguments for message's format' --- @see utils.fprintf -function utils.quit(code,...) - if type(code) == 'string' then - utils.fprintf(io.stderr,code,...) - code = -1 - else - utils.fprintf(io.stderr,...) - end - io.stderr:write('\n') - os.exit(code) -end - ---- print an arbitrary number of arguments using a format. --- @param fmt The format (see string.format) --- @param ... Extra arguments for format -function utils.printf(fmt,...) - utils.assert_string(1,fmt) - utils.fprintf(stdout,fmt,...) -end - ---- write an arbitrary number of arguments to a file using a format. --- @param f File handle to write to. --- @param fmt The format (see string.format). --- @param ... Extra arguments for format -function utils.fprintf(f,fmt,...) - utils.assert_string(2,fmt) - f:write(format(fmt,...)) -end - -local function import_symbol(T,k,v,libname) - local key = rawget(T,k) - -- warn about collisions! - if key and k ~= '_M' and k ~= '_NAME' and k ~= '_PACKAGE' and k ~= '_VERSION' then - utils.printf("warning: '%s.%s' will not override existing symbol\n",libname,k) - return - end - rawset(T,k,v) -end - -local function lookup_lib(T,t) - for k,v in pairs(T) do - if v == t then return k end - end - return '?' -end - -local already_imported = {} - ---- take a table and 'inject' it into the local namespace. --- @param t The Table --- @param T An optional destination table (defaults to callers environment) -function utils.import(t,T) - T = T or _G - t = t or utils - if type(t) == 'string' then - t = require (t) - end - local libname = lookup_lib(T,t) - if already_imported[t] then return end - already_imported[t] = libname - for k,v in pairs(t) do - import_symbol(T,k,v,libname) - end -end - -utils.patterns = { - FLOAT = '[%+%-%d]%d*%.?%d*[eE]?[%+%-]?%d*', - INTEGER = '[+%-%d]%d*', - IDEN = '[%a_][%w_]*', - FILE = '[%a%.\\][:%][%w%._%-\\]*' -} - ---- escape any 'magic' characters in a string --- @param s The input string -function utils.escape(s) - utils.assert_string(1,s) - return (s:gsub('[%-%.%+%[%]%(%)%$%^%%%?%*]','%%%1')) -end - ---- return either of two values, depending on a condition. --- @param cond A condition --- @param value1 Value returned if cond is true --- @param value2 Value returned if cond is false (can be optional) -function utils.choose(cond,value1,value2) - if cond then return value1 - else return value2 - end -end - -local raise - ---- return the contents of a file as a string --- @param filename The file path --- @param is_bin open in binary mode --- @return file contents -function utils.readfile(filename,is_bin) - local mode = is_bin and 'b' or '' - utils.assert_string(1,filename) - local f,err = io.open(filename,'r'..mode) - if not f then return utils.raise (err) end - local res,err = f:read('*a') - f:close() - if not res then return raise (err) end - return res -end - ---- write a string to a file --- @param filename The file path --- @param str The string --- @return true or nil --- @return error message --- @raise error if filename or str aren't strings -function utils.writefile(filename,str) - utils.assert_string(1,filename) - utils.assert_string(2,str) - local f,err = io.open(filename,'w') - if not f then return raise(err) end - f:write(str) - f:close() - return true -end - ---- return the contents of a file as a list of lines --- @param filename The file path --- @return file contents as a table --- @raise errror if filename is not a string -function utils.readlines(filename) - utils.assert_string(1,filename) - local f,err = io.open(filename,'r') - if not f then return raise(err) end - local res = {} - for line in f:lines() do - append(res,line) - end - f:close() - return res -end - ---- split a string into a list of strings separated by a delimiter. --- @param s The input string --- @param re A Lua string pattern; defaults to '%s+' --- @param plain don't use Lua patterns --- @param n optional maximum number of splits --- @return a list-like table --- @raise error if s is not a string -function utils.split(s,re,plain,n) - utils.assert_string(1,s) - local find,sub,append = string.find, string.sub, table.insert - local i1,ls = 1,{} - if not re then re = '%s+' end - if re == '' then return {s} end - while true do - local i2,i3 = find(s,re,i1,plain) - if not i2 then - local last = sub(s,i1) - if last ~= '' then append(ls,last) end - if #ls == 1 and ls[1] == '' then - return {} - else - return ls - end - end - append(ls,sub(s,i1,i2-1)) - if n and #ls == n then - ls[#ls] = sub(s,i1) - return ls - end - i1 = i3+1 - end -end - ---- split a string into a number of values. --- @param s the string --- @param re the delimiter, default space --- @return n values --- @usage first,next = splitv('jane:doe',':') --- @see split -function utils.splitv (s,re) - return unpack(utils.split(s,re)) -end - ---- convert an array of values to strings. --- @param t a list-like table --- @param temp buffer to use, otherwise allocate --- @param tostr custom tostring function, called with (value,index). --- Otherwise use `tostring` --- @return the converted buffer -function utils.array_tostring (t,temp,tostr) - temp, tostr = temp or {}, tostr or tostring - for i = 1,#t do - temp[i] = tostr(t[i],i) - end - return temp -end - ---- execute a shell command and return the output. --- This function redirects the output to tempfiles and returns the content of those files. --- @param cmd a shell command --- @param bin boolean, if true, read output as binary file --- @return true if successful --- @return actual return code --- @return stdout output (string) --- @return errout output (string) -function utils.executeex(cmd, bin) - local mode - local outfile = os.tmpname() - local errfile = os.tmpname() - - if utils.dir_separator == '\\' then - outfile = os.getenv('TEMP')..outfile - errfile = os.getenv('TEMP')..errfile - end - cmd = cmd .. [[ >"]]..outfile..[[" 2>"]]..errfile..[["]] - - local success, retcode = utils.execute(cmd) - local outcontent = utils.readfile(outfile, bin) - local errcontent = utils.readfile(errfile, bin) - os.remove(outfile) - os.remove(errfile) - return success, retcode, (outcontent or ""), (errcontent or "") -end - ---- 'memoize' a function (cache returned value for next call). --- This is useful if you have a function which is relatively expensive, --- but you don't know in advance what values will be required, so --- building a table upfront is wasteful/impossible. --- @param func a function of at least one argument --- @return a function with at least one argument, which is used as the key. -function utils.memoize(func) - return setmetatable({}, { - __index = function(self, k, ...) - local v = func(k,...) - self[k] = v - return v - end, - __call = function(self, k) return self[k] end - }) -end - - -utils.stdmt = { - List = {_name='List'}, Map = {_name='Map'}, - Set = {_name='Set'}, MultiMap = {_name='MultiMap'} -} - -local _function_factories = {} - ---- associate a function factory with a type. --- A function factory takes an object of the given type and --- returns a function for evaluating it --- @tab mt metatable --- @func fun a callable that returns a function -function utils.add_function_factory (mt,fun) - _function_factories[mt] = fun -end - -local function _string_lambda(f) - local raise = utils.raise - if f:find '^|' or f:find '_' then - local args,body = f:match '|([^|]*)|(.+)' - if f:find '_' then - args = '_' - body = f - else - if not args then return raise 'bad string lambda' end - end - local fstr = 'return function('..args..') return '..body..' end' - local fn,err = utils.load(fstr) - if not fn then return raise(err) end - fn = fn() - return fn - else return raise 'not a string lambda' - end -end - ---- an anonymous function as a string. This string is either of the form --- '|args| expression' or is a function of one argument, '_' --- @param lf function as a string --- @return a function --- @usage string_lambda '|x|x+1' (2) == 3 --- @usage string_lambda '_+1 (2) == 3 --- @function utils.string_lambda -utils.string_lambda = utils.memoize(_string_lambda) - -local ops - ---- process a function argument. --- This is used throughout Penlight and defines what is meant by a function: --- Something that is callable, or an operator string as defined by <code>pl.operator</code>, --- such as '>' or '#'. If a function factory has been registered for the type, it will --- be called to get the function. --- @param idx argument index --- @param f a function, operator string, or callable object --- @param msg optional error message --- @return a callable --- @raise if idx is not a number or if f is not callable -function utils.function_arg (idx,f,msg) - utils.assert_arg(1,idx,'number') - local tp = type(f) - if tp == 'function' then return f end -- no worries! - -- ok, a string can correspond to an operator (like '==') - if tp == 'string' then - if not ops then ops = require 'pl.operator'.optable end - local fn = ops[f] - if fn then return fn end - local fn, err = utils.string_lambda(f) - if not fn then error(err..': '..f) end - return fn - elseif tp == 'table' or tp == 'userdata' then - local mt = getmetatable(f) - if not mt then error('not a callable object',2) end - local ff = _function_factories[mt] - if not ff then - if not mt.__call then error('not a callable object',2) end - return f - else - return ff(f) -- we have a function factory for this type! - end - end - if not msg then msg = " must be callable" end - if idx > 0 then - error("argument "..idx..": "..msg,2) - else - error(msg,2) - end -end - ---- bind the first argument of the function to a value. --- @param fn a function of at least two values (may be an operator string) --- @param p a value --- @return a function such that f(x) is fn(p,x) --- @raise same as @{function_arg} --- @see func.bind1 -function utils.bind1 (fn,p) - fn = utils.function_arg(1,fn) - return function(...) return fn(p,...) end -end - ---- bind the second argument of the function to a value. --- @param fn a function of at least two values (may be an operator string) --- @param p a value --- @return a function such that f(x) is fn(x,p) --- @raise same as @{function_arg} -function utils.bind2 (fn,p) - fn = utils.function_arg(1,fn) - return function(x,...) return fn(x,p,...) end -end - - ---- assert that the given argument is in fact of the correct type. --- @param n argument index --- @param val the value --- @param tp the type --- @param verify an optional verfication function --- @param msg an optional custom message --- @param lev optional stack position for trace, default 2 --- @raise if the argument n is not the correct type --- @usage assert_arg(1,t,'table') --- @usage assert_arg(n,val,'string',path.isdir,'not a directory') -function utils.assert_arg (n,val,tp,verify,msg,lev) - if type(val) ~= tp then - error(("argument %d expected a '%s', got a '%s'"):format(n,tp,type(val)),lev or 2) - end - if verify and not verify(val) then - error(("argument %d: '%s' %s"):format(n,val,msg),lev or 2) - end -end - ---- assert the common case that the argument is a string. --- @param n argument index --- @param val a value that must be a string --- @raise val must be a string -function utils.assert_string (n,val) - utils.assert_arg(n,val,'string',nil,nil,3) -end - -local err_mode = 'default' - ---- control the error strategy used by Penlight. --- Controls how <code>utils.raise</code> works; the default is for it --- to return nil and the error string, but if the mode is 'error' then --- it will throw an error. If mode is 'quit' it will immediately terminate --- the program. --- @param mode - either 'default', 'quit' or 'error' --- @see utils.raise -function utils.on_error (mode) - if ({['default'] = 1, ['quit'] = 2, ['error'] = 3})[mode] then - err_mode = mode - else - -- fail loudly - if err_mode == 'default' then err_mode = 'error' end - utils.raise("Bad argument expected string; 'default', 'quit', or 'error'. Got '"..tostring(mode).."'") - end -end - ---- used by Penlight functions to return errors. Its global behaviour is controlled --- by <code>utils.on_error</code> --- @param err the error string. --- @see utils.on_error -function utils.raise (err) - if err_mode == 'default' then return nil,err - elseif err_mode == 'quit' then utils.quit(err) - else error(err,2) - end -end - ---- is the object of the specified type?. --- If the type is a string, then use type, otherwise compare with metatable --- @param obj An object to check --- @param tp String of what type it should be -function utils.is_type (obj,tp) - if type(tp) == 'string' then return type(obj) == tp end - local mt = getmetatable(obj) - return tp == mt -end - -raise = utils.raise - ---- load a code string or bytecode chunk. --- @param code Lua code as a string or bytecode --- @param name for source errors --- @param mode kind of chunk, 't' for text, 'b' for bytecode, 'bt' for all (default) --- @param env the environment for the new chunk (default nil) --- @return compiled chunk --- @return error message (chunk is nil) --- @function utils.load - ---------------- --- Get environment of a function. --- With Lua 5.2, may return nil for a function with no global references! --- Based on code by [Sergey Rozhenko](http://lua-users.org/lists/lua-l/2010-06/msg00313.html) --- @param f a function or a call stack reference --- @function utils.getfenv - ---------------- --- Set environment of a function --- @param f a function or a call stack reference --- @param env a table that becomes the new environment of `f` --- @function utils.setfenv - ---- execute a shell command. --- This is a compatibility function that returns the same for Lua 5.1 and Lua 5.2 --- @param cmd a shell command --- @return true if successful --- @return actual return code --- @function utils.execute - -return utils - - |