if-statement

问题 I'm having trouble with a dust if condition. I have a partial that points to 2 different dust templates depending on the Country code {>"receipt/merchantInfo/merchantInfo_{countryCode}"/} I'm trying to make an if else condition that will figure out if the {countryCode} is US. Example: {@if cond="'{countryCode}' == 'US'"} <p>is country code US</p> {:else} <p>is NOT country code US</p> {/if} This isn't working. Anyone have an idea where I went wrong with this? 回答1: The @if helper has been

问题 In the C programming language, it is my understanding that variables can only be defined at the beginning of a code block, and the variable will have the scope of the block it was declared in. With that in mind, I was wondering whether it is considered bad practice to artificially create a new scope as in this example: void foo() { ... Do some stuff ... if(TRUE) { char a; int b; ... Do some more stuff ... } ... Do even more stuff ... } Assuming TRUE is set to 1 in a macro definition, would

问题 In the C programming language, it is my understanding that variables can only be defined at the beginning of a code block, and the variable will have the scope of the block it was declared in. With that in mind, I was wondering whether it is considered bad practice to artificially create a new scope as in this example: void foo() { ... Do some stuff ... if(TRUE) { char a; int b; ... Do some more stuff ... } ... Do even more stuff ... } Assuming TRUE is set to 1 in a macro definition, would

问题 I have a for loop in Matlab, and all the code inside the for loop is enclosed in an if statement. For example : for p = 1:length(array) if array(p) == 1 %// Test positive for condition %// Generic code here that %// Only executes if p == 1 end; end; Is it faster to have test for equality using an if statement, and execute the interior code if true, or, to test for inequality and then use a continue statement, such as : for p = 1:length(array) if array(p) ~= 1 %// Test negative for condition

问题 Could you tell my why the following isnt working in postgres sql?: See updated code below UPDATE: I expect the query to return "0.30" as float. This construct is only for testing purposes, i have some complex querys which depend on this conditional structure... BUt i dont know how to fix it.. Result is: ERROR: syntax error at or near "1" LINE 4: if 1=1 then UPDATE: This construction appears in a function... so I want to do following: CREATE FUNCTION f_test(myvalue integer) RETURNS float AS $$

问题 So let's make a quick example. my_list = [ {"name": "toto", "value": 3}, {"name": "foo", "value": 42}, {"name": "bar", "value": 56} ] def foo(name): try: value = next(e["value"] for e in my_list if e["name"] == name) except StopIteration: print "Uuuh not found." else: if value % 2: print "Odd !" else: print "Even !" As you can see, the above code works : >>> foo("toto") Odd ! >>> foo("foo") Even ! >>> foo("kappa") Uuuh not found. I was just wondering if there is a particular reason about why

问题 Best example would be to show you how is this solved in Javascript: var someString = someEmptyString || 'new text value'; In this javascript example, we have detected that 'someEmptyString' is empty and automatically set the value to 'new text value'. Is this possible in PHP and what's the shortest (code) way to do it? This is how I do it now: if ($someEmptyString == "") $someString = 'new text value'; else $someString = $someEmptyString; This is bugging me for quite some time and I would be

问题 Best example would be to show you how is this solved in Javascript: var someString = someEmptyString || 'new text value'; In this javascript example, we have detected that 'someEmptyString' is empty and automatically set the value to 'new text value'. Is this possible in PHP and what's the shortest (code) way to do it? This is how I do it now: if ($someEmptyString == "") $someString = 'new text value'; else $someString = $someEmptyString; This is bugging me for quite some time and I would be

问题 Basically to make this quick and simple, I'm looking to run an XOR conditional in django template. Before you ask why don't I just do it in the code, this isn't an option. Basically I need to check if a user is in one of two many-to-many objects. req.accepted.all and req.declined.all Now they can only be in one or the other (hence the XOR conditional). From the looking around on the docs the only thing I can figure out is the following {% if user.username in req.accepted.all or req.declined

问题 I simplified the code. The following three are work. for /L %a in (1,1,9) do @(if %a NEQ 0 (echo %a)) & for /L %a in (1,1,9) do @(if not %a == 0 (echo %a)) & (for /L %a in (1,1,9) do @(if not %a == 0 (echo %a)))|sort /R But the next one didn't work, (for /L %a in (1,1,9) do @(if %a NEQ 0 (echo %a)))|sort /R What's the problem of NEQ in the piped block command? more simplified, This works, (if 3 == 3 echo yes)|sort This doesn't work, (if 3 NEQ 2 echo yes)|sort Part of my code. @echo off