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README.md

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+# purescript-postgresql-client
+
+purescript-postgresql-client is a PostgreSQL client library for PureScript.
+Included is a preprocessor, purspgpp, which finds embedded SQL queries in
+PureScript source files and infers their types. Such queries can be written as
+follows:
+
+```purescript
+userName = [query|
+    SELECT first_name, last_name
+    FROM users
+    WHERE id = $1
+|]
+```
+
+purspgpp will replace this by something like the following:
+
+```purescript
+(Query """
+    SELECT first_name, last_name
+    FROM users
+    WHERE id = $1
+""" :: Query (UUID × Unit) (String × String × Unit))
+```
+
+You can integrate purspgpp into your build system. For example, here is a
+PowerShell script that executes it for all `.purspg` files:
+
+```powershell
+Get-ChildItem src -Recurse -Filter *.purspg `
+| ForEach-Object {
+    perl6 `
+        bower_components/purescript-postgresql-client/purspgpp `
+        "user=postgres password=lol123 dbname=nn" `
+        "$($_.FullName)" `
+        "$([IO.Path]::ChangeExtension($_.FullName, "purs"))"
+    if (!$?) {
+        Write-Error "Unable to preprocess $_"
+    }
+}
+```