Tutorial by Examples: var

To reference a variable in a query, add a colon (:) before the variable name. Datetime targetDate = Datetime.now().addDays(-7); List<Lead> recentLeads = [SELECT Id FROM Lead WHERE CreatedDate > :targetDate]; string targetName = 'Unknown'; List<Contact> incompleteContacts = [SELE...

Add following Paths to the PATH-Enviromentvariable [Path to CMake]\bin [Path to Git]\bin [Path to SDK]\tools [Path to SDK]\platform-tools [Path to NDK] [Path to ANT]\bin [Path to MinGW]\bin [Path to MinGW]\msys\1.0\bin [Path to Java jre]\bin [Path to Java jdk]\bin Make sure you use ba...

You can check if a variable has been defined in a scope by using ColdFusion's built in StructKeyExists() function. This can be used inside a <cfif> tag to prevent error messages in the event you attempt to refer to a variable that does not exist. You can also use this function to determine whe...

This is a very basic feature selection technique. Its underlying idea is that if a feature is constant (i.e. it has 0 variance), then it cannot be used for finding any interesting patterns and can be removed from the dataset. Consequently, a heuristic approach to feature elimination is to first re...

When multiple variables are defined at the beginning of the batch, a short definition form may be used by employing a replacement string. @echo off set "vars=_A=good,_B=,_E=bad,_F=,_G=ugly,_C=,_H=,_I=,_J=,_K=,_L=,_D=6 set "%vars:,=" & set "%" for /f %%l in ('set _'...

/*- * * The default VCL code. * * NB! You do NOT need to copy & paste all of these functions into your * own vcl code, if you do not provide a definition of one of these * functions, the compiler will automatically fall back to the default * code from this file. * */ sub vcl...

/* * The built-in (previously called default) VCL code. * * NB! You do NOT need to copy & paste all of these functions into your * own vcl code, if you do not provide a definition of one of these * functions, the compiler will automatically fall back to the default * code from this f...

It is possible to create a set of variables that can act similar to an array (although they are not an actual array object) by using spaces in the SET statement: @echo off SET var=A "foo bar" 123 for %%a in (%var%) do ( echo %%a ) echo Get the variable directly: %var% Result: ...

Here are some ways to set variables: You can set a variable to a specific, string, number, date using SET EX: SET @var_string = 'my_var'; SET @var_num = '2' SET @var_date = '2015-07-20'; you can set a variable to be the result of a select statement using := EX: Select @var := '123'; (...

C99 Since C99, C has variable length arrays, VLA, that model arrays with bounds that are only known at initialization time. While you have to be careful not to allocate too large VLA (they might smash your stack), using pointers to VLA and using them in sizeof expressions is fine. double sumAll(si...

It is possible to query an object about its instance variables using instance_variables, instance_variable_defined?, and instance_variable_get, and modify them using instance_variable_set and remove_instance_variable: class Foo attr_reader :bar def initialize @bar = 42 end end f = F...

The Kernel exposes methods for getting the list of global_variables and local_variables: cats = 42 $demo = "in progress" p global_variables.sort #=> [:$!, :$", :$$, :$&, :$', :$*, :$+, :$,, :$-0, :$-F, :$-I, :$-K, :$-W, :$-a, #=> :$-d, :$-i, :$-l, :$-p, :$-v, :$-w, :$...

Classes and modules have the same methods for introspecting instance variables as any other object. Class and modules also have similar methods for querying the class variables (@@these_things): p Module.methods.grep(/class_variable/) #=> [:class_variables, :class_variable_get, :remove_class_va...

It is a common practice to set application variables to an object scope. This keeps them easy to identify and distinguish from variables in other scopes. The Variables scope in a CFC is private to the CFC. When you set variables in this scope, they cannot be seen by pages that invoke the CFC. <...

%storemagic stores variables and macros on IPython's database. To automatically restore stored variables at startup add this to ipython_config.py: c.StoreMagic.autorestore = True Example: In [1]: l = ['hello',10,'world'] In [2]: %store l In [3]: exit (IPython session is closed and started...

C99 Macros with variadic args: Let's say you want to create some print-macro for debugging your code, let's take this macro as an example: #define debug_print(msg) printf("%s:%d %s", __FILE__, __LINE__, msg) Some examples of usage: The function somefunc() returns -1 if failed and 0 ...

To concatenate the value of two or more variables into a single string and print it as the output, we need to make use of interpolation. The following Less code, #demo:after { @var1: Hello; @var2: World!!!; content: "@{var1} @{var2}"; } when compiled would set "Hello Wo...

This creates a variant (a tagged union) that can store either an int or a string. std::variant< int, std::string > var; We can store one of either type in it: var = "hello"s; And we can access the contents via std::visit: // Prints "hello\n": visit( [](auto&&a...

This does not cover allocators. struct A {}; struct B { B()=default; B(B const&)=default; B(int){}; }; struct C { C()=delete; C(int) {}; C(C const&)=default; }; struct D { D( std::initializer_list<int> ) {}; D(D const&)=default; D()=default; }; std::variant<A,B> var_ab...

In R, data objects are manipulated using named data structures. The names of the objects might be called "variables" although that term does not have a specific meaning in the official R documentation. R names are case sensitive and may contain alphanumeric characters(a-z,A-z,0-9), the dot...