Minor fixes and version info

LF-3212

CHANGELOG.md

@@ -3,6 +3,11 @@
 This log documents significant changes for each release.  This project follows
 [Semantic Versioning](http://semver.org/).
 
+## [3.15.3] - 2025-01-09
+### Fixed
+- Read environment variables only when they are used in an expression, avoiding
+  unnecessary getter calls when working with libraries like Jotai.
+
 ## [3.15.2] - 2024-08-30
 ### Fixed
 - Removed the need to run `(cd demo && npm ci)`.

README.md

@@ -55,7 +55,7 @@ These will define additional global variables like "fhirpath_dstu2_model",
 Evaluating FHIRPath:
 
 ```js
-evaluate(resourceObject, fhirPathExpression, environment, model, options);
+evaluate(resourceObject, fhirPathExpression, envVars, model, options);
 ```
 where:
 * resourceObject - FHIR resource, part of a resource (in this case
@@ -65,7 +65,7 @@ where:
   or object, if fhirData represents the part of the FHIR resource:
     * fhirPathExpression.base - base path in resource from which fhirData was extracted
     * fhirPathExpression.expression - FHIRPath expression relative to path.base
-* environment - a hash of variable name/value pairs.
+* envVars - a hash of variable name/value pairs.
 * model - the "model" data object specific to a domain, e.g. R4.
   For example, you could pass in the result of require("fhirpath/fhir-context/r4");
 * options - additional options:
@@ -154,7 +154,7 @@ the option "resolveInternalTypes" = false:
 
 ```js
 const contextVariable = fhirpath.evaluate(
-  resource, expression, context, model, {resolveInternalTypes: false}
+  resource, expression, envVars, model, {resolveInternalTypes: false}
 );
 ```
 
@@ -181,7 +181,7 @@ In the next example, `res` will have a value like this:
 
 ```js
 const res = fhirpath.types(
-  fhirpath.evaluate(resource, expression, context, model, {resolveInternalTypes: false})
+  fhirpath.evaluate(resource, expression, envVars, model, {resolveInternalTypes: false})
 );
 ```
 
@@ -191,7 +191,7 @@ let tracefunction = function (x, label) {
   console.log("Trace output [" + label + "]: ", x);
 };
 
-const res = fhirpath.evaluate(contextNode, path, environment, fhirpath_r4_model, { traceFn: tracefunction });
+const res = fhirpath.evaluate(contextNode, path, envVars, fhirpath_r4_model, { traceFn: tracefunction });
 ```
 
 ### Asynchronous functions

package.json

@@ -1,6 +1,6 @@
 {
   "name": "fhirpath",
-  "version": "3.15.2",
+  "version": "3.15.3",
   "description": "A FHIRPath engine",
   "main": "src/fhirpath.js",
   "types": "src/fhirpath.d.ts",

src/fhirpath.d.ts

@@ -7,7 +7,7 @@ export function compile<T extends OptionVariants>(
 export function evaluate<T extends OptionVariants>(
   fhirData: any,
   path: string | Path,
-  context?: Context,
+  envVars?: Context,
   model?: Model,
   options?: T
 ): ReturnType<T>;
@@ -66,7 +66,7 @@ type ReturnType<T> =
     T extends NoAsyncOptions ? any[] :
     any[] | Promise<any[]>;
 
-type Compile<T> = (resource: any, context?: Context) => ReturnType<T>;
+type Compile<T> = (resource: any, envVars?: Context) => ReturnType<T>;
 
 type Context = void | Record<string, any>;
 

src/fhirpath.js

@@ -705,7 +705,7 @@ function parse(path) {
  * @param {(object|object[])} resource -  FHIR resource, bundle as js object or array of resources
  *  This resource will be modified by this function to add type information.
  * @param {object} parsedPath - a special object created by the parser that describes the structure of a fhirpath expression.
- * @param {object} context - a hash of variable name/value pairs.
+ * @param {object} envVars - a hash of variable name/value pairs.
  * @param {object} model - The "model" data object specific to a domain, e.g. R4.
  *  For example, you could pass in the result of require("fhirpath/fhir-context/r4");
  * @param {object} options - additional options:
@@ -722,7 +722,7 @@ function parse(path) {
  *   RESTful API that is used to create %terminologies that implements
  *   the Terminology Service API.
  */
-function applyParsedPath(resource, parsedPath, vars, model, options) {
+function applyParsedPath(resource, parsedPath, envVars, model, options) {
   constants.reset();
   let dataRoot = util.arraify(resource).map(
     i => i?.__path__
@@ -742,7 +742,7 @@ function applyParsedPath(resource, parsedPath, vars, model, options) {
       context: dataRoot
     },
     processedUserVarNames: new Set(),
-    vars: vars || {},
+    vars: envVars || {},
     model
   };
   if (options.traceFn) {
@@ -843,7 +843,7 @@ function resolveInternalTypes(val) {
  *  or object, if fhirData represents the part of the FHIR resource:
  * @param {string} path.base - base path in resource from which fhirData was extracted
  * @param {string} path.expression - FHIRPath expression relative to path.base
- * @param {object} [context] - a hash of variable name/value pairs.
+ * @param {object} [envVars] - a hash of variable name/value pairs.
  * @param {object} [model] - The "model" data object specific to a domain, e.g. R4.
  *  For example, you could pass in the result of require("fhirpath/fhir-context/r4");
  * @param {object} [options] - additional options:
@@ -862,8 +862,8 @@ function resolveInternalTypes(val) {
  *   RESTful API that is used to create %terminologies that implements
  *   the Terminology Service API.
  */
-function evaluate(fhirData, path, context, model, options) {
-  return compile(path, model, options)(fhirData, context);
+function evaluate(fhirData, path, envVars, model, options) {
+  return compile(path, model, options)(fhirData, envVars);
 }
 
 /**
@@ -924,7 +924,7 @@ function compile(path, model, options) {
 
   if (typeof path === 'object') {
     const node = parse(path.expression);
-    return function (fhirData, context) {
+    return function (fhirData, envVars) {
       if (path.base) {
         let basePath = model.pathsDefinedElsewhere[path.base] || path.base;
         const baseFhirNodeDataType = model && model.path2Type[basePath];
@@ -934,14 +934,14 @@ function compile(path, model, options) {
       }
       // Globally set model before applying parsed FHIRPath expression
       TypeInfo.model = model;
-      return applyParsedPath(fhirData, node, context, model, options);
+      return applyParsedPath(fhirData, node, envVars, model, options);
     };
   } else {
     const node = parse(path);
-    return function (fhirData, context) {
+    return function (fhirData, envVars) {
       // Globally set model before applying parsed FHIRPath expression
       TypeInfo.model = model;
-      return applyParsedPath(fhirData, node, context, model, options);
+      return applyParsedPath(fhirData, node, envVars, model, options);
     };
   }
 }