Portions of the source file outside of such tags is not treated as executable code and is echoed to standard out. Python blocks begin with a line that ends in a colon. The block ends with the first line that is not indented further than the initial line. Python raises an IndentationError if the statements in the block that are not in a nested block are not all indented the same.

Using tabs in Python source code is unrecommended and many editors replace them automatically with spaces. If the Python interpreter encounters a tab, it is treated as 8 spaces. A blank line terminates the block. Colons are also used to separate keys from values in dictionary literals and in sequence slice notation. A matched curly bracket pair can be replaced by the do and end keywords. By convention curly brackets are used for one line blocks.

The end keyword also terminates blocks started by defclassor module. The following code is legal:. Putting a newline in these strings results in a syntax error. There is however a multi-line string literal which starts and ends with three single quotes ''' or three double quotes: Putting a newline before the comma or associator results in a syntax error. Setting the source code encoding makes it possible to safely use non-ASCII characters in string literals and regular expression literals.

How to declare variables which are local to the scope defining region which immediately contain them. Variables do not need to be declared and there is no syntax for declaring a local variable. If a variable with no previous reference is accessed, its value is NULL.

A variable is created by assignment if one does not already exist. If the variable is inside a function or method, then its scope is the body of the function or method. Otherwise it is a global. Variables are created by assignment. A lower case name can refer to a local variable or method. If both are defined, the local variable takes precedence. To invoke the method make the receiver explicit: However, outside of class and modules local variables hide functions because functions are private methods in the class Object.

Assignment to name will create a local variable if one with that name does not exist, even if there is a method name. A variable is global if it is used at the top level i. A function must use the global keyword to access the global variable. A variable is global if it is defined at the top level of a file i. Although the variable is global, it must be imported individually or be prefixed with the module name prefix to be accessed from another file.

To be accessed from inside a function or method it must be declared with the global keyword. The ruby interpreter does not prevent modification of constants, it only gives a warning.

Capitalized variables are globally visible, but a full or relative namespace name must be used to reach them: If the variable on the left has not previously been defined in the current scope, then it is created.

This may hide a variable in a containing scope. Assignment does not return a value and cannot be used in an expression. Assignments can nevertheless be chained to assign a value to multiple variables:. Assignment operators have right precedence and evaluate to the right argument, so they can be chained.

If the variable on the left does not exist, then it is created. Nested sequences of expression can be assigned to a nested sequences of l-values, provided the nesting matches. This assignment will set a to 1, b to 2, and c to Compound assignment operators mutate a variable, setting it to the value of an operation which takes the previous value of the variable as an argument.

Python compound assignment operators do not return a value and hence cannot be used in expressions. The C-style increment and decrement operators can be used to increment or decrement values.

They return values and thus can be used in expressions. The prefix versions return the value in the variable after mutation, and the postfix version return the value before mutation. Incrementing a value two or more times in an expression makes the order of evaluation significant:.

Ruby mostly avoids the problem by providing a non-mutating increment and decrement. However, here is a Ruby expression which is dependent on order of evaluation:. The increment and decrement operators also work on strings. There are postfix versions of these operators which evaluate to the value before mutation:. The Integer class defines succpredand nextwhich is a synonym for succ. The String class defines succsucc!

In particular, the following comparisons are true:. PHP does not provide the programmer with a mechanism to distinguish an undefined variable from a variable which has been set to NULL. How to write a conditional expression. A ternary operator is an operator which takes three arguments. Any identifier which matches TRUE case-insensitive can be used for the TRUE boolean. When converted to a string for display purposes, TRUE renders as "1" and FALSE as "".

Examples of conditional contexts are the conditional clause of an if statement and the test of a while loop. Most of the relational operators will convert a string to a number if the other operand is a number.

In general if A i are expressions and op i are relational operators, then. The operators for addition, subtraction, multiplication, float division, integer division, modulus, and exponentiation. Trigonometric functions are in radians unless otherwise noted. Logarithms are natural unless otherwise noted. Ruby also has Math.

To compute the log of x for base buse. How to truncate a float to the nearest integer towards zero; how to round a float to the nearest integer; how to find the nearest integer above a float; how to find the nearest integer below a float; how to take the absolute value.

Require the library mathn and integer division will yield rationals instead of truncated integers. Most of the functions in math have analogues in cmath which will work correctly on complex numbers. How to generate a random integer between 0 and 99, include, float between zero and one in a uniform distribution, or a float in a normal distribution with mean zero and standard deviation one.

All the languages in the sheet set the seed automatically to a value that is difficult to predict. The Ruby MRI interpreter uses the current time and process ID, for example. As a result there is usually no need to set the seed.

Setting the seed to a hardcoded value yields a random but repeatable sequence of numbers. This can be used to ensure that unit tests which cover code using random numbers doesn't intermittently fail. The seed is global state. If multiple functions are generating random numbers then saving and restoring the seed may be necessary to produce a repeatable sequence. How to convert integers to strings of digits of a given base. How to convert such strings into integers. Python has the functions binoctand hex which take an integer and return a string encoding the integer in base 2, 8, and A separate unicode type is available for working with Unicode strings.

In Python 3 the str type supports multibtye characters and the unicode type has been removed.

There is a mutable bytearray type and an immutable bytes type for working with sequences of bytes. The String type supports multibtye characters. All strings have an explicit Encoding. In Python 2, these create unicode strings instead of str strings.

Since the Python 2 unicode type corresponds to the Python 3 str type, portable code will use the u prefix. How to specify custom delimiters for single and double quoted strings. These can be used to avoid backslash escaping. Newlines are not permitted in single quote and double quote string literals. A string can continue onto the following line if the last character on the line is a backslash.

In this case, neither the backslash nor the newline are taken to be part of the string. Triple quote literals, which are string literals terminated by three single quotes or three double quotes, can contain newlines:.

When string literals have an r or R prefix there are no backslash escape sequences and any backslashes thus appear in the created string. The delimiter can be inserted into a string if it is preceded by a backslash, but the backslash is also inserted.

It is thus not possible to create a string with an r or R prefix that ends in a backslash. The r and R prefixes can be used with single or double quotes:. Unicode literals have a u prefiix:.

This syntax is also available in Python 3. Here documents are strings terminated by a custom identifier. They perform variable substitution and honor the same backslash escapes as double quoted strings. Python lacks variable interpolation in strings. Triple quotes honor the same backslash escape sequences as regular quotes, so triple quotes can otherwise be used like here documents:.

Put the customer identifier in single quotes to prevent variable interpolation and backslash escape interpretation:. When used with named parameters str. If the replacement fields appear in sequential order and aren't repeated, the numbers can be omitted:. How to define a UTF-8 aware version of ucfirst. This version also puts the rest of the string in lowercase:.

Rails monkey patches the String class with the titleize method for capitalizing the words in a string. PHP converts a scalar to the desired type automatically and does not raise an error if the string contains non-numeric data.

If the start of the string is not numeric, the string evaluates to zero in a numeric context. Methods for splitting a string into three parts using the first or last occurrence of a substring:. How to find the index of the leftmost occurrence of a substring in a string; how to find the index of the rightmost occurrence.

The languages in this reference sheet do not have character literals, so characters are represented by strings of length one. In Python 2, the string of lowercase letters is in string. In Python 2, the maketrans function is in the module string instead of str. How to remove all specified characters from a string; how to remove all but the specified characters from a string.

Regular expressions or regexes are a way of specifying sets of strings. If a string belongs to the set, the string and regex "match". Regexes can also be used to parse strings. The modern notation for regexes was introduced by Unix command line tools in the s.

POSIX standardized the notation into two types: Perl regexes are extended regexes augmented by new character class abbreviations and a few other features introduced by the Perl interpreter in the s. All the languages in this sheet use Perl regexes. Any string that doesn't contain regex metacharacters is a regex which matches itself.

The regex metacharacters are: A character class is a set of characters in brackets: When used in a regex it matches any character it contains.

Such a character class matches its complement; that is, any character not inside the brackets. The hyphen is used to specify character ranges: When the hyphen is first or last inside the brackets it matches itself. The backslash can be used to escape the above characters or the terminal character class delimiter: It can be used in character class abbreviations or string backslash escapes.

In all languages the period can be made to match all characters. PHP uses the m modifier. Python uses the re. Ruby uses the s modifier. A vertical pipe takes as its arguments everything up to the next vertical pipe, enclosing paren, or end of string. Parentheses control the scope of alternation and the quantifiers described below. They are also used for capturing groups, which are the substrings which matched parenthesized parts of the regular expression.

Each language numbers the groups and provides a mechanism for extracting them when a match is made. A parenthesized subexpression can be removed from the groups with this syntax: As an argument quantifiers take the preceding regular character, character class, or group.

When there is a choice, greedy quantifiers will match the maximum possible number of occurrences of the argument. Lazy quantifiers match the minimum possible number. To match a metacharacter, put a backslash in front of it. To match a backslash use two backslashes. These include the split function and functions which start with ereg. The literal for a regular expression; the literal for a regular expression with a custom delimiter.

PHP regex literals are strings. The first character is the delimiter and it must also be the last character. Python does not have a regex literal, but the re. Each major category is subdivided into multiple minor categories. Each minor category has a two letter code, where the first letter is the major category. For example, Nd is "Number, decimal digit".

When variables any project report on fundamental analysis on stock market involved it is safer to invoke the Regexp method because string variables are more likely to contain nil.

Python modifiers are bit flags. To use more than one flag at the same time, join them with bit or: How to replace all occurrences of a matching pattern in a string with the provided substitution string.

The gsub operator returns a copy of the string with the substitution made, if any. The sub and sub! How to get the substring that matched the regular expression, as well as the part of the string before and after the matching substring.

Ruby has syntax for extracting a group from a match in a single expression. The following evaluates to "":.

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How to get the substrings which matched the parenthesized parts of a regular expression and put them into a dictionary. For reference, we call the?

PHP originally supported Python-style named groups since that was the style that was added to the PCRE regex engine. Perl-style named groups were added to PHP 5.

How to use backreferences in a regex; how to use backreferences in the replacement string of substitution. In ISO terminology, a date specifies a day in the Gregorian calendar and a time does not contain date information; it merely specifies a time of day. A data type which combines both date and time information is convenient, but ISO doesn't provide a name for based business home make money work at home telecom an entity.

PHP, Python, and C use the compound noun datetime for combined date and time values and we adopt it here as a generic term. An useful property of ISO dates, times, and datetimes is that they are correctly ordered by a lexical sort on their string representations. This is because they are big-endian the year is the leftmost element and they used fixed-length, zero-padded fields with numerical values for each term in the string representation.

The C standard library provides two methods for representing dates. The first is the Unix epochwhich is the seconds since the beginning of January 1, in UTC. If such a time were stored in a bit signed integer, the rollover would happen on January 18, The Unix epoch is an example of a serial datetimein which the value is stored as a single numeric value representing the difference in time in some unit from a specially designated datetime called the epoch.

Another serial datetime is the Windows file timewhich is the number of nanosecond intervals since the beginning of January 1, UTC. It was introduced when journaling was added to NTFS 777 vip binary options signals service reviews part of the Windows launch. Some serial datetimes use days as the unit. The Excel serial number is the number of days since December 31, The Julian day numberused in astronomy, is the number of days since November 24, BCE in the proleptic Gregorian calendar.

Julian days start at noon GMT. A broken-down datetime uses multiple numeric values to represent the components of a calendar date and time. The Linux man pages call the tm struct a "broken-down" date and time, whereas the BSD man pages call it a "broken-out" date and time. The first day in the Gregorian calendar was 15 October The proleptic Gregorian calendar is an extension of the Gregorian calendar to earlier dates.

When such dates are used, they should be called out to be precise. The epoch in the proleptic Gregorian calendar is the yearalso written 1 AD or 1 CE. The previous year is the yearalso written 1 BC or 1 BCE. The year before that is the yearalso written 2 BC or 2 BCE. The ISO standard recommends that years before or after be written with a plus or minus sign prefix.

An ordinal date is a broken-down date consisting of a year, followed by the day of the year. The How to make money with non performing notes standard recommends that it be written in YYYY-DDD or YYYYDDD format.

A week date is a type of calendar which uses the year, week of the year, and day of the week to refer to to dates. In the ISO week date, the first week of the year is the week starting from Monday which contains January 4th. An ISO week date can thus have a different year number than the corresponding Gregorian date. The first week of the year is numbered 01and the first day of the week, Monday, is numbered 1. Weeks are written in YYYY-Www-D or YYYYWwwD format, where the upper case W is literal.

Common years have days and leap years have days. The extra day in February 29th. Leap years are years divisible by 4 but notor years divisible by Because the length of a solar day is irregular, leap seconds are occasionally used to keep things in sync. This is accomplished by occasionally adding a leap second to the end of June 30th or December 31st. The system also allows for removing the last second of June 30th or December 31st, though as of this hasn't been done.

Is forex trading a get rich quick business uses and exposes the tm struct of the C standard library. Python has a module called time which is a thin wrapper to the standard library functions which operate on this struct. Here is how get a tm 60 second binary options scam ladder in Python:.

How to convert a datetime type to the Unix epoch which is the number of seconds since the start of January 1, UTC. The Python datetime object created by now and utcnow has no timezone information associated with it.

The strftime method assumes a receiver with no time zone information represents a local time. Thus it is an error to call strftime on the return value of utcnow.

Replacing now with utcnow in the first way, or utcnow with now in the second way produces an incorrect value. The format specifiers used by the strftime function from the standard C library earnest money mortgage contract definition the Unix date command:.

PHP supports strftime but it also has its own time formatting system used by dateDateTime:: The letters used in the PHP time formatting system are described here.

How to parse a datetime using the format notation of the strptime function from the standard C library. ISO distinguishes between a time interval, which is defined by two datetime endpoints, and a duration, which is the length forex eur chf live a time interval and can be defined by replicate binary option unit of time such as '10 minutes'.

A time interval can also be defined by date and time representing the start of the interval and a duration. ISO defines notation for durations. This notation starts with a 'P' and uses a 'T' to separate the day and larger units from the hour and smaller units.

Binary options trading nedir the location relative to the 'T' is important for interpreting the letter 'M', which is used forex glossary of terms both months and minutes.

Do datetime values include time zone information. When a datetime value for the local time is created, how the local time zone is determined. To examine it from delta short put option command line use zdump:. Timezones are often identified by three or four letter abbreviations. Many of the abbreviations do not uniquely identify a time zone. Furthermore many of the time zones have been altered in the past.

The Olson database aka Tz database decomposes the world into zones in which oil forex trading forums local clocks have all been set to the same time since automatic successfully trade binary options it gives penny stock trading apps zones unique names.

The Time class has a zone method which returns the time zone abbreviation for the object. There is a tzinfo gem which can be used to create time zone objects using the Olson database name. This can in turn be used to convert between UTC visual effects softwares list and local times which are daylight saving aware. How to get the microseconds easy way to make money in nfs carbon of a combined date and time value.

The C standard library uses the letter u as an abbreviation for micro. How to put the process to sleep for a specified number of seconds. In Python and Ruby the default version of sleep supports a fractional number of seconds. Python has the mutable list and the immutable tuple. Ruby provides an Array datatype. The quote words operator, which is a literal for arrays of strings where each string contains a single word. How to slice a subarray from an array by specifying a start index and an end index; how to slice a subarray from an array by specifying an offset index and a length index.

Slices can leave the first or last index unspecified, in which case the first or last index of the sequence is used:. The third argument in the colon-delimited slice argument can be negative, which reverses the order of calculating cost basis of stock options result:.

These operations can be used to use the array as a stack. They can be used with the operations that manipulate the back of the array to use the array as a queue. How to create an array by concatenating two arrays; how to modify an array by concatenating another array to the end of it. After a shallow copy is made, the addition, removal, or replacement of elements in the copy does not modify of the original array.

However, if elements in the copy are modified, those elements are also modified in the original array. A deep copy is a recursive copy. The original array is copied and a deep copy is performed on all elements of the array.

No change to the contents of the copy will modify jquery create dynamic select options contents of the original array. The slice operator can be used in this manner on strings and tuples but there is little incentive to do so since both are immutable.

Like the slice operator copy. Python 3 ranges and Ruby marsh stock options implement some of the functionality of arrays without allocating space to hold all the elements.

How to create a replicate binary option copy of an array, and how to sort an array in place. Also, how to set the comparison function when sorting. In Python 3 the cmp parameter was removed.

One can achieve the same effect by defining cmp method on the class of the list element. Python sets support the leninand for operators. It may be more efficient to work with the result of the set constructor directly rather than convert it back to a coles anzac day opening hours cairns. How to compute the relative complement of two arrays or sets; how to compute the symmetric difference.

If an element is in the right argument, then it will not be in the return value even if it is contained in the left argument multiple times. How to test whether a condition holds for all members of an array; how to test whether a condition holds for at least one member of any array. A universal test is always true for an empty array. An existential test is always false for an empty array. A existential test can readily be implemented with a filter. A universal test can also be implemented with a filter, but it is more work: The result can easily be converted to a random sample of array values:.

When nested arrays are flattened by one level, the depth of each element which is not in the top level array is reduced by one. Flattening nested arrays completely leaves no nested arrays. This is equivalent to extracting the leaf nodes of a tree. How to interleave arrays. In the case of two arrays the result is an array of pairs or an commodity option trading strategies list.

How to check for the presence of a key in a dictionary without raising an exception. Distinguishes from the case where the key is present but mapped to null or a value which evaluates to false.

How to create a dictionary from an array of pairs; how to create a dictionary from an even length array. In the examples, if the dictionaries d1 and d2 share keys then the values from d2 will be used in the merged dictionary.

How to turn a dictionary into its inverse. If a key 'foo' is mapped to value 'bar' by a dictionary, then its inverse will map the key 'bar' to the value 'foo'. However, if multiple keys are mapped to the same value in the original dictionary, then some of the keys will be discarded in the inverse.

In Python 3 dict.

How to convert the keys of a dictionary to an array; how to convert the values of a dictionary to an array. The following code illustrates the change in behavior:. How to create a dictionary with a default value for missing keys; how to compute and store the value on lookup. Python has both functions and methods.

Ruby only has methods: Perl subroutines can be invoked with a function syntax or a method syntax. Parens are mandatory, even for functions which take no arguments. Omitting the parens returns the function or method as an object. Whitespace can occur between the function name and the following left paren. Ruby parens are optional. Leaving out the parens results in ambiguity when function invocations are nested.

The interpreter resolves the ambiguity by assigning as many arguments as possible to the innermost function invocation, regardless of its actual arity. It is mandatory that the left paren not be separated from the method name by whitespace.

Perl passes the elements of arrays as individual arguments. In the following invocation, the function foo does not know which arguments came from which array. For that matter it does not know how many arrays were used in the invocation:. This function accepts one or more arguments. Invoking it without any arguments raises a TypeError:. Invoking it without any arguments raises an ArgumentError:. The caller can use named parameter syntax at the point of invocation even if the function was defined using positional parameters.

In a function invocation, the splat can be used to expand an array into separate arguments. In a function invocation, the double splat expands a dictionary into named parameters. A double splat operator can be used to force the caller to use named parameter syntax. This method has the disadvantage that spelling errors in the parameter name are not caught:.

Python lambdas cannot contain newlines or semicolons, and thus are limited to a single statement or expression. Unlike named functions, the value of the last statement or expression is returned, and a return is not necessary or permitted.

Lambdas are closures and can refer to local variables in scope, even if they are returned from that scope. A nested function can be returned and hence be invoked outside of its containing function, but it is not visible by its name outside of its containing function.

With respect to control words, Proc objects behave like blocks and lambdas like functions. In particular, when the body of a Proc object contains a return or break statement, it acts like a return or break in the code which invoked the Proc object.

A return in a lambda merely causes the lambda to exit, and a break inside a lambda must be inside an appropriate control structure contained with the lambda body. If a variable containing a string is used like a function then PHP will look for a function with the name in the string and attempt to invoke it. Python function are stored in variables by default.

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As a result a function and a variable with the same name cannot share the same scope. This is also the reason parens are mandatory when invoking Python functions. Here is a technique for creating private state which exploits the fact that the expression for a default value is evaluated only once:.

How to create a first class function with access to the local variables of the local scope in which it was created. Python 2 has limited closures: Python 3 permits write access to local variables outside the immediate scope when declared with nonlocal.

An iterator is an object with two methods: Python sequences, of which lists are an example, define an iter for returned an iterator which traverses the sequence. A decorator replaces an invocation of one function with another in a way that that is imperceptible to the client. Normally a decorator will add a small amount of functionality to the original function which it invokes.

A decorator can modify the arguments before passing them to the original function or modify the return value before returning it to the client. Or it can leave the arguments and return value unmodified but perform a side effect such as logging the call. The operator module provides functions which perform the same operations as the various operators.

Using these functions is more efficient than wrapping the operators in lambdas. All operators can be invoked with method invocation syntax. The binary operator invocation syntax can be regarded as syntactic sugar. If an if statement is the last statement executed in a function, the return value is the value of the branch that executed. Ruby if statements are expressions. They can be used on the right hand side of assignments:.

PHP provides a do-while loop. The body of such a loop is guaranteed to execute at least once. A continue statement skips ahead to the next iteration of a while or for loop.

Ruby has a throw keyword in addition to raise. PHP code must specify a variable name for the caught exception. Exception is the top of the exception hierarchy and will catch all exceptions.

Internal PHP functions usually do not throw exceptions. They can be converted to exceptions with this signal handler:. A rescue Exception clause will catch any exception. A rescue clause with no exception type specified will catch exceptions that are subclasses of StandardError. Exceptions outside StandardError are usually unrecoverable and hence not handled in code.

In a rescue clause, the retry keyword will cause the begin clause to be re-executed. If the exception is assigned to a variable in the except clause and the variable is used as the argument to raisethen a new stack trace is created.

If the exception is assigned to a variable in the rescue clause and the variable is used as the argument to raisethen the original stack trace is preserved. A block of statements that is guaranteed to be executed even if an exception is thrown or caught.

Ruby MRI threads are operating system threads, but a global interpreter lock prevents more than one thread from executing Ruby code at a time. The PHP interpreter is packaged in 3 different ways: The latter executable is called PHP CLI. From the perspective of a PHP programmer, there no important differences between PHP CGI and PHP SAPI. LanguageStandard Library 3.

LanguageStandard Library. Python uses leading whitespace to indicate block structure. When tabs and spaces are mixed a tab is equal to 8 spaces. The command line options '-t' and '-tt' will warn and raise an error respectively when tabs are mixed with spaces.

There are two basic sequence types: List literals use square brackets and commas [1, 2, 3]; tuple literals use parens and commas 1 ,2, 3. Python has sets; set literals use curly brackets and commas: Dictionaries and sets are implemented using hash tables so dictionary keys and set elements must be hashable.

All values that can be stored in a variable and passed to functions as arguments are objects in the sense that they have methods which can be invoked using the method syntax. Attributes are settable by default. Methods must declare the receiver as the first argument. Classes, methods, functions, and modules are objects. Ruby has a type of value called a symbol. The literal syntax for a symbol is: Symbols can be used to pass functions or methods as arguments by name.

They can be used as keys in Hash objects in place of strings, but the client must remember the type of the keys since: Also note that converting a Hash object with symbols as keys to JSON and then back will yield a Hash object with strings as keys.

In Ruby all values that can be stored in a variable and passed to functions as arguments are objects in the sense that they have methods which can be invoked using the method syntax. Moreover classes are objects. The system provided classes are open and as a result the user can add methods to classes such as StringArrayor Fixnum.

Ruby only permits single inheritance, but Ruby modules are mix-ins and can be used to add methods to a class via the include statement. Ruby methods can be declared private and this is enforced by the interpreter. Object attributes are private by default and attribute names have an ampersand prefix.

When invoking a method the parens are optional. If there are two or more arguments they must still be separated by commas. If one of the arguments is an expression containing a method invocation with arguments, then the Ruby interpreter will assign as many arguments as possible to the innermost method invocation.

Inside a Ruby method, the self keyword refers to the receiver. It is not declared when defining the method. Ruby functions are implemented as methods on an object called main which has the special property that any methods defined on it become instance methods in the Object class which is a base class of most Ruby objects. This makes the method available everywhere. Methods defined at the top level are also added to the main object and the Object class.

Functions which Ruby provides by default are instance methods defined the Object class or the Kernel module. Ruby methods are not objects and cannot directly be stored in variables.

It is worth emphasizing that the Python interpreter when encountering a method identifier with no parens returns the method as an object value, but the Ruby interpreter invokes the method. As mentioned earlier, methods can be passed by name using symbols. If a method receives a symbol representing a method as an argument, it can invoke the method with the syntax: Although passing a method or a function is a bit awkward, Ruby provides a convenient mechanism called blocks for simultaneously defining an anonymous function at the invocation of a method and providing it to the method as an argument.

The invoked method can in turn invoke the block with the yield keyword. Ruby blocks are closures like lambda functions and can see local variables in the enclosing scope in which they were defined. The parameters of the block are local to the block. Semicolon syntax is available so that identifiers listed after the arguments could be made local to the block even if already defined in the containing scope.

The lambda keyword or the Proc. The function can be invoked with variable. If such a function is passed to a method argument as the last argument and preceded with an ampersand, the function will be used as the block for the method.

Conversely, if the last argument in a method definition is preceded with an ampersand, any block provided to the function will be bound to the argument name as an anonymous function. There are literals for Infinity and NaN. DomainError unless require 'complex' is in effect. A is in effect. General category values e. Morever, they can be used inside character classes. U is in effect. ADD3 1, 2, 3 ; add3 1, 2, 3 add3 1, 2, 3 parens are optional: If invoked with new and return value not an object, returns this.

Exception BaseException User-defined exceptions should subclass Exception. In Python 2 old-style classes can be thrown. Exception User-defined exceptions should subclass StandardError.

The function phpversion will return the version number as a string. The following function will return the version number as a string: Returns Infinity, NaN, or -Infinity depending upon sign of dividend. POSIX character classes such as [[: DateInterval object if diff method used: DateTime objects can be instantiated without specifying the time zone if a default is set: ADD3 1, 2, 3.

BaseException User-defined exceptions should subclass Exception. In Ruby or when m modifier is used also matches right side of a newline.

In Ruby or when m modifier is used also matches left side of a newline. Upper case letters match lower case letters and vice versa.