Block represents a pre-processable block which looks like the following: It is delimited by ~~~ and contains a command to be run along with the input

Block represents a code block.

Language represents a programming language with it Extension and Commands to execute its programs.

Meta contains all of the data to be parsed out of a markdown file's header section

Model is an interface for models.model, so that cycle imports are avoided

Model represents the model of this presentation, which contains all the state related to the current slides.

Result represents the output for an executed code block.

Search represents the current search

Server is the server for hosting this presentation.

State tracks the current buffer, page, and total number of slides

cmds: Multiple commands; placeholders can be used Placeholders <file>, <name> and <path> can be used.

Temporary structure to differentiate values not present in the YAML header from values set to empty strings in the YAML header. We replace values not