diff options
Diffstat (limited to 'README.adoc')
| -rw-r--r-- | README.adoc | 18 |
1 files changed, 6 insertions, 12 deletions
diff --git a/README.adoc b/README.adoc index ade07f2..c31b576 100644 --- a/README.adoc +++ b/README.adoc @@ -51,10 +51,9 @@ For a slightly more realistic example have a look at 'greet.ell'. Runtime ------- -All variables are put in a single global namespace with no further scoping. -Arguments to a block (which is a list of lists) must be assigned to variables -first using the `arg` special form, and that must happen before they get -overriden by execution of a different block. +Variables use per-block dynamic scoping. Arguments to a block (which is a list +of lists) must be assigned to variables first using the `arg` special form, and +that must happen before they get overriden by execution of a different block. When evaluating a command, the first argument is typically a string with its name and it is resolved as if `set` was called on it. @@ -69,8 +68,9 @@ Returns the arguments without any evaluation. `arg [<name>]...` -Assigns arguments to the current call in order to given names. -Names for which there are no values left are set to `[]`. +Assigns arguments to the current block in order to given names. Names for which +there are no values left default to `[]`. This form can effectively be used to +declare local variables. Standard library ---------------- @@ -167,12 +167,6 @@ Install development packages for GNU Readline to get a REPL for toying around: Possible Ways of Complicating ----------------------------- - * variable scoping: lexical scoping is deemed too complex. The simplest is to - look up and set values in the nearest dynamic scope they can be found in, - or globally if not found, and have `arg` create the scopes, which also makes - AWK-style local variables work. A convention of starting locally bound names - with an underscore can keep the global namespace always accessible, and even - overridable if needed. * reference counting: currently all values are always copied as needed, which is good enough for all imaginable use cases, simpler and less error-prone |