The Let Function File. Maker Development Company. Among File. Maker Pros many functions, the Let function stands out as one of, if not the most, powerful among them. This article attempts to demystify the Let function and demonstrate examples of its practical use. Details on the next available live FileMaker training class from Cris Ippolite of lynda. Make your own app without extensive development experience or IT skills with the FileMaker Platform. Manage contacts, assets, content, and more. FM Starting Point is a completely FREE FileMaker template designed for use with FileMaker Pro 16, and is focused on small businesses, work groups, and nonprofit. Filemaker Pro 6 Download Free' title='Filemaker Pro 6 Download Free' />Free shared trial then from 100 per year Latest version 16, 15 14 servers free setup secure fast reliable. UK based FileMaker hosting. Pro, Go. New Mailit 6 for FileMaker 1016. Click here to see what is new in Mailit 6 and for upgrade information. Product Info The Ultimate Email PlugIn. Integrate full. Home Font Encoders FileMaker Pro Barcode Plugin Font Encoder and Tutorial. FileMaker Pro Barcode Font Encoder Plugin. Generate barcodes in FileMaker databases. Learn software, creative, and business skills to achieve your personal and professional goals. Join today to get access to thousands of courses. Purpose of the Let function. Sets a variables to the result of an expression for the duration of a calculation, script or in the case of global variables, until the file is closed. Why use the Let functionAllows the user to assign the results of an expression to a variable and then return a result all within a single function. Aids in the reduction or elimination of nested andor repeated expressions and functions which improves readability and performance. Format. File. Maker Pro 1. Let function as such. Letvar. 1expression. From File. Makers help documentation the parameters of the Let function are defined as such var any variable name, local variable name or global variable name. KeepVid Pro Mac is the best video downloader application that lets you quickly and easily download videos from thousands of video sharing sites. Bento was a database application for Mac OS X made by FileMaker Inc. Bento differs significantly from the companys flagship product, FileMaker Pro, in that it relies. Filemaker Pro 6 Download Free' title='Filemaker Pro 6 Download Free' />Note In order to make it more readable I have separated the format into multiple lines. This convention is not required but makes it easier to discuss in this article. Also please note that you can include comments using the characters. I should also note that though File. Maker includes the curly braces in their description of the format they are not required and are present to denote the option of making multiple variable assignments. If you only have a single variable you can omit the brackets. See the code samples below. Multiple Variable Assignments include square bracketsLet. This is a comment. Single Variable Assignment no square bracketsLet. This is a comment. Variable Types. Its important to remember that Let supports three variable types calculation, script and global. Let statement. script scope a  valid for the duration of the calculation in which it is defined or the script in which the calculation is evaluated. The Let statement below illustrates the assignment of each variable type. It is also important to note that even though they all share the name a they are NOT the same variable. The absence or inclusion of the or denote separate variable spaces. So be sure you do not confuse them when you are writing a calculation. I am a calculation level variable. I am a script variable. I am a global variable. Basic Use. Here are some examples of the Let statement in use. Here I assign values to variables a 1 and b 2. Then I use the defined variable in a calculation expression a b. The result of the calculation is returned as the result of the expression. If a 1 and b 2 then a b 3. So the value returned from the Let statement is 3. For the next example we will assume the following script steps preceded our Let statement. Set Variable a 1. Set Variable b 1. I am using variables that were assigned in the above script steps. Let statement. Set Variable result Let. Use Let to Avoid Nesting. In this example we try a more real world scenario to demonstrate how Let helps us avoid nesting and repetition. First lets try parsing some text without using the Let function. In this case, we are trying to get everything after the first sentence using the position of the first period. Right Sample Data Paragraph Length Sample Data Paragraph Position Sample Data Paragraph. This calculation statement is difficult to read due to the nested Position and Length functions. It might make sense 6 minutes after its written but what about when you come back in 6 days, 6 months or even 6 years later. Youll have to take a close look at it to understand whats going on. Here is the solution using the Let function. Sample Data Paragraph. Length Lengthsource. Position Position source. Right source source. Length start. Position. In this example the statement is longer but is more readable. Each line handles only one function. Libre Calc Gantt on this page. It can easily be read from top to bottom without the confusion of using nested functions. When you revisit this calculation you wont be scratching your head trying to remember how it works. Youll be able to read it. Use Let to Avoid Repetition. In this example I am creating an expression, part of which I will need to use more than once. Heres how it works without the aid of the Let statement. Sample Data Quantity Sample Data Amount Sample Data Quantity Sample Data Amount ample Data Discount Percentage. Again, this statement is hard to read due to nesting. Also notice the reuse of the expression Sample Data Quantity Sample Data Amount which appears twice and causes the statement to be longer than it needs to be and contributes to the statements cluttered appearance. Another problem is that if we need to change the Sample Data Quantity Sample Data Amount expression well need to do so in multiple places. Now here is the same calculation using the Let statement. Sample Data Quantity. Sample Data Amount. Percentage Sample Data Discount Percentage. Total subtotal discount. Percentage. Like the previous example this is much easier to read since each line performs a single function. If you want to change an expression you can do it in one place without having to hunt though the code for duplicate expressions. Nesting Let Functions. File. Maker Pro will allow you to nest Let statements. However, if you make a calculation scope variable assignment in a nested Let statement it will only be available within the Let statement in which it was defined. If you want to make variable assignments that are available to the outer Let statement then use a script level variable var or a global variable var. Let a0 a. In the above example the returned result a is equal to 1 even though the assignment was made in the nested Let. The reason is that the a used in the nested Let only has calculation level scope and therefore the assignment is only valid within the nested Let statement. If we change the a to be a script level variable by the use of a single then the returned result will be different. Let. b Let a0 a. The above example now returns a as 0. This is because the scope of a is now at the script level. Any assignment made to that variable will be true until the enclosing script has completed. Dynamic Variable Creation. When combined with the Evaluate function Let can be used to create variables dynamically. Imagine you have a table that contains a list of things that you need to reference regularly. These items may not change on a regular basis and might be considered constants. For example you might have a list of strings used for localization within a solution used in multiple regions. In this case you might want to have constants that are defined at launch time that correspond to the users region. Imagine you have a table called Strings which contains 3 fields Name, String and Region. Now imagine that upon launch the system could do a find on the Strings table to get all the strings for a given region. You could then loop over the records and use a Let statement to dynamically create a global variable to store the constant for each record. Strings Name Strings String. After this calculation is run on a given record a variable corresponding to the records Name field variable will be created. Welcome then the variable name would be Welcome the contents of the variable would be whatever was in the String field.