Formula language

<h2 id="development">Development</h2>
<p>It was created by <a href="/facts/Ray_Ozzie/DfoWwaXo">Ray Ozzie</a> during the early development of Lotus Notes. He borrowed the compiler and decompiler from the <a href="/facts/Lotus_1-2-3/tnkvSG3M">Lotus 1-2-3</a> spreadsheet, but unlike the spreadsheet language Formula Language was designed primarily for string and list processing, not numerical processing.  It was originally a <a href="/facts/Functional_programming/cdxqPEIM">Functional programming</a> language with unique text list-handling features inspired by Ray Ozzie's prior use of <a href="/facts/Icon_(programming_language)/J7QHUDqq">Icon</a> and <a href="/facts/Lisp_(programming_language)/xJHA3CrX">Lisp</a>.
</p><p>The Formula language engine was rewritten by Damien Katz for Notes and Domino 6.<a class="footnote-ref" id="fnref:1" href="#fn:1"><sup>1</sup></a> New features were added to the language, such as looping and dynamic execution, and performance was improved.<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a>
</p>
<h2 id="structure">Structure</h2>
<p>The Formula language has two parts:
</p>
<ul><li><i>@Functions</i> for calculations and simple logic</li>
<li><i>@Commands</i> for performing actions in the user interface</li></ul>
<p><i>@Functions</i> can be used in several places throughout Lotus Notes. The most important uses are:
</p>
<ul><li>to select documents to show to the user in a view (a kind of index) or to select documents for further processing. In this case, the formula will evaluate to a 'true' (selected) or 'false' value (not selected) for each document.</li>
<li>to provide default values for fields, to transform the data entered by the user (like stripping off redundant spaces) and to validate this data.</li>
<li>to get a list of values from a Notes database or even from a relational database (using <a href="/facts/ODBC/2dV2Fm5j">ODBC</a>). This may be used to provide a user with a list of values to choose from.</li>
<li>to process a set of documents. The formula is placed in an agent, a program or macro that can be started by a user or by the Notes server according to a schedule. When the agent is triggered, the formula executes for each selected document (this a very limited form of a loop). This is an efficient way to change many documents, if the logic is not too complicated. In case of complicated changes, <a href="/facts/LotusScript/rzfyXtSM">LotusScript</a> is used.</li></ul>
<p><i>@Commands</i> are like menu commands: they perform actions in the Lotus Notes client. Examples of actions are:
</p>
<ul><li>opening a Notes database</li>
<li>creating an e-mail</li>
<li>putting the cursor in a specific data-entry field</li>
<li>closing a window</li>
<li>starting an agent</li></ul>
<p>@Commands are primarily used in formulas that are triggered by user action, such as in button formulas. It is possible to combine them with @Functions, for example by making execution of an @command conditional on a field value.
</p>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>Damien Katz (January 4, 2005). "Formula Engine Rewrite". Personal blog. Retrieved September 30, 2016. <a href="http://www.damienkatz.net/2005/01/formula-engine-rewrite.html" target="_blank">http://www.damienkatz.net/2005/01/formula-engine-rewrite.html</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>"Enhancements to the formula language in Domino 6". IBM. November 4, 2002. Archived from the original on October 22, 2012. Retrieved September 30, 2016. <a href="https://web.archive.org/web/20121022162650/https://www.ibm.com/developerworks/lotus/library/ls-formula_enhancements/" target="_blank">https://web.archive.org/web/20121022162650/https://www.ibm.com/developerworks/lotus/library/ls-formula_enhancements/</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
</ol>

Formula language open-in-new

Formula language