Gqlgen generates strings that conform to the XML encoded BNF grammar contained in the GQL Standard.
Gqlgen is written in Go. Follow the Go installation instructions to install Go.
Run the following command from the Gqlgen source directory.
go build
This will build Gqlgen and install the executable in the Gqlgen source directory. The program will be named "gqlgen" on Unix varients, including OS X or will be name "gqlgen.exe" on Windows
| Argument Name | Type | Default | Description |
|---|---|---|---|
| bnf | string | ./bnf.xml | Filename of the XML file containing the GQL BNF Grammar |
| start | string | GQL-program | Start rule name |
| cnt | integer | 1 | Number of strings to generate |
| v | none | false | If specified run in verbose mode |
Gqlgen generates strings that conform to the whole language or to subsets of the language. The start parameter specifies the rule name to use as the starting point for generating strings. For example, to generate s, set start to "value expression", as is shown in the following example.
./gqlgen -start "value expression"
To generate more than one string at a time, use the cnt argument to specify the number of strings, as show in the following example.
./gqlgen -start "value expression" -cnt 5
Gqlgen makes random choices to decide which altertives to use, whether to include an optional rule, and how many times to repeat repeated rules. To avoid endless recursion a limit of 6 is used. When that limit is exceeded, Gqlgen retries the string creation.
Currently, Gqlgen is rather naive in terms of picking alternatives. This leads to the case that Gqlgen rarely chooses some alternatives. One critical example is that Gqlgen usually chooses Session commands over procedure definitions. The most effective way to use Gqlgen is to specify a start rule. For example, the following command generates 5 s. The results are shown.
./gqlgen -start "value expression" -cnt 5
TABLE "LòD`Z¶Xxá`4sXv`ŹzPP0LUj4UXòH`zlOnòVBuŹ_8OŨáváD"
Ues IS TYPED PATH NOT NULL AND NOT ( NOT ALL_DIFFERENT (w,DCkO) IS TRUE ) IS TRUE
uTrU0
SAME (qka,zC,jj9Up,W) IS NOT FALSE OR NOT EXZ IS SOURCE OF LevjU IS NOT FALSE AND NOT w IS DESTINATION OF pX IS NOT UNKNOWN
q
Each string is separated by a newline.